diff --git a/src/backend/datasources/filters/AsciiFilter.cpp b/src/backend/datasources/filters/AsciiFilter.cpp
index 6179e422f..4bc38a111 100644
--- a/src/backend/datasources/filters/AsciiFilter.cpp
+++ b/src/backend/datasources/filters/AsciiFilter.cpp
@@ -1,2945 +1,2950 @@
 /***************************************************************************
 File                 : AsciiFilter.cpp
 Project              : LabPlot
 Description          : ASCII I/O-filter
 --------------------------------------------------------------------
 Copyright            : (C) 2009-2018 Stefan Gerlach (stefan.gerlach@uni.kn)
 Copyright            : (C) 2009-2017 Alexander Semke (alexander.semke@web.de)
 
 ***************************************************************************/
 
 /***************************************************************************
 *                                                                         *
 *  This program is free software; you can redistribute it and/or modify   *
 *  it under the terms of the GNU General Public License as published by   *
 *  the Free Software Foundation; either version 2 of the License, or      *
 *  (at your option) any later version.                                    *
 *                                                                         *
 *  This program is distributed in the hope that it will be useful,        *
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of         *
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the          *
 *  GNU General Public License for more details.                           *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the Free Software           *
 *   Foundation, Inc., 51 Franklin Street, Fifth Floor,                    *
 *   Boston, MA  02110-1301  USA                                           *
 *                                                                         *
 ***************************************************************************/
 #include "backend/datasources/LiveDataSource.h"
 #include "backend/core/column/Column.h"
 #include "backend/core/Project.h"
 #include "backend/datasources/filters/AsciiFilter.h"
 #include "backend/datasources/filters/AsciiFilterPrivate.h"
 #include "backend/worksheet/plots/cartesian/CartesianPlot.h"
 #include "backend/worksheet/plots/cartesian/XYCurve.h"
 #include "backend/lib/macros.h"
 #include "backend/lib/trace.h"
 
 #ifdef HAVE_MQTT
 #include "backend/datasources/MQTTClient.h"
 #include "backend/datasources/MQTTTopic.h"
 #endif
 
 #include <QTextStream>
 #include <KLocalizedString>
 #include <KFilterDev>
 #include <QProcess>
 #include <QDateTime>
 
 /*!
 \class AsciiFilter
 \brief Manages the import/export of data organized as columns (vectors) from/to an ASCII-file.
 
 \ingroup datasources
 */
 AsciiFilter::AsciiFilter() : AbstractFileFilter(), d(new AsciiFilterPrivate(this)) {}
 
 AsciiFilter::~AsciiFilter() = default;
 
 /*!
   reads the content of the device \c device.
 */
 void AsciiFilter::readDataFromDevice(QIODevice& device, AbstractDataSource* dataSource, AbstractFileFilter::ImportMode importMode, int lines) {
 	d->readDataFromDevice(device, dataSource, importMode, lines);
 }
 
 void AsciiFilter::readFromLiveDeviceNotFile(QIODevice &device, AbstractDataSource* dataSource) {
 	d->readFromLiveDevice(device, dataSource);
 }
 
 qint64 AsciiFilter::readFromLiveDevice(QIODevice& device, AbstractDataSource* dataSource, qint64 from) {
 	return d->readFromLiveDevice(device, dataSource, from);
 }
 
 #ifdef HAVE_MQTT
 /*!
   reads the content of a message received by the topic.
 */
 void AsciiFilter::readMQTTTopic(const QString& message, const QString& topic, AbstractDataSource*dataSource) {
 	d->readMQTTTopic(message, topic, dataSource);
 }
 
 /*!
   provides a preview of the data received by the topic.
 */
 void AsciiFilter::MQTTPreview(QVector<QStringList>& list, const QString& message, const QString& topic) {
 	d->MQTTPreview(list, message, topic);
 }
 
 /*!
   Returns the statistical data, that the MQTTTopic needs for the will message.
 */
 QString AsciiFilter::MQTTColumnStatistics(const MQTTTopic* topic) const{
 	return d->MQTTColumnStatistics(topic);
 }
 
 /*!
   Returns the column mode of the last column (the value column of the MQTTTopic).
 */
 AbstractColumn::ColumnMode AsciiFilter::MQTTColumnMode() const{
 	return d->MQTTColumnMode();
 }
 
 /*!
   After the MQTTTopic is loaded, prepares the filter for reading.
 */
 void AsciiFilter::setPreparedForMQTT(bool prepared, MQTTTopic* topic, const QString& separator) {
 	d->setPreparedForMQTT(prepared, topic, separator);
 }
 #endif
 
 /*!
   returns the separator used by the filter.
 */
 QString AsciiFilter::separator() const {
 	return d->separator();
 }
 
 /*!
   returns the separator used by the filter.
 */
 int AsciiFilter::isPrepared() {
 	return d->isPrepared();
 }
 
 /*!
   reads the content of the file \c fileName.
 */
 void AsciiFilter::readDataFromFile(const QString& fileName, AbstractDataSource* dataSource, AbstractFileFilter::ImportMode importMode) {
 	d->readDataFromFile(fileName, dataSource, importMode);
 }
 
 QVector<QStringList> AsciiFilter::preview(const QString& fileName, int lines) {
 	return d->preview(fileName, lines);
 }
 
 QVector<QStringList> AsciiFilter::preview(QIODevice &device) {
 	return d->preview(device);
 }
 
 /*!
   reads the content of the file \c fileName to the data source \c dataSource.
 */
 //void AsciiFilter::read(const QString& fileName, AbstractDataSource* dataSource, AbstractFileFilter::ImportMode importMode) {
 //	d->read(fileName, dataSource, importMode);
 //}
 
 
 /*!
 writes the content of the data source \c dataSource to the file \c fileName.
 */
 void AsciiFilter::write(const QString& fileName, AbstractDataSource* dataSource) {
 	d->write(fileName, dataSource);
 // 	emit()
 }
 
 /*!
   loads the predefined filter settings for \c filterName
 */
 void AsciiFilter::loadFilterSettings(const QString& filterName) {
 	Q_UNUSED(filterName);
 }
 
 /*!
   saves the current settings as a new filter with the name \c filterName
 */
 void AsciiFilter::saveFilterSettings(const QString& filterName) const {
 	Q_UNUSED(filterName);
 }
 
 /*!
   returns the list with the names of all saved
   (system wide or user defined) filter settings.
 */
 QStringList AsciiFilter::predefinedFilters() {
 	return QStringList();
 }
 
 /*!
   returns the list of all predefined separator characters.
 */
 QStringList AsciiFilter::separatorCharacters() {
 	return (QStringList() << "auto" << "TAB" << "SPACE" << "," << ";" << ":"
 	        << ",TAB" << ";TAB" << ":TAB" << ",SPACE" << ";SPACE" << ":SPACE" << "2xSPACE" << "3xSPACE" << "4xSPACE" << "2xTAB");
 }
 
 /*!
 returns the list of all predefined comment characters.
 */
 QStringList AsciiFilter::commentCharacters() {
 	return (QStringList() << "#" << "!" << "//" << "+" << "c" << ":" << ";");
 }
 
 /*!
 returns the list of all predefined data types.
 */
 QStringList AsciiFilter::dataTypes() {
 	const QMetaObject& mo = AbstractColumn::staticMetaObject;
 	const QMetaEnum& me = mo.enumerator(mo.indexOfEnumerator("ColumnMode"));
 	QStringList list;
 	for (int i = 0; i <= 100; ++i)	// me.keyCount() does not work because we have holes in enum
 		if (me.valueToKey(i))
 			list << me.valueToKey(i);
 	return list;
 }
 
 QString AsciiFilter::fileInfoString(const QString& fileName) {
 	QString info(i18n("Number of columns: %1", AsciiFilter::columnNumber(fileName)));
 	info += QLatin1String("<br>");
 	info += i18n("Number of lines: %1", AsciiFilter::lineNumber(fileName));
 	return info;
 }
 
 /*!
     returns the number of columns in the file \c fileName.
 */
 int AsciiFilter::columnNumber(const QString& fileName, const QString& separator) {
     KFilterDev device(fileName);
 	if (!device.open(QIODevice::ReadOnly)) {
 		DEBUG("Could not open file " << fileName.toStdString() << " for determining number of columns");
 		return -1;
 	}
 
 	QString line = device.readLine();
 	line.remove(QRegExp("[\\n\\r]"));
 
 	QStringList lineStringList;
 	if (separator.length() > 0)
 		lineStringList = line.split(separator);
 	else
 		lineStringList = line.split(QRegExp("\\s+"));
 	DEBUG("number of columns : " << lineStringList.size());
 
 	return lineStringList.size();
 }
 
 size_t AsciiFilter::lineNumber(const QString& fileName) {
 	KFilterDev device(fileName);
 
 	if (!device.open(QIODevice::ReadOnly)) {
 		DEBUG("Could not open file " << fileName.toStdString() << " to determine number of lines");
 
 		return 0;
 	}
 	if (!device.canReadLine())
 		return -1;
 
 	size_t lineCount = 0;
 	while (!device.atEnd()) {
 		device.readLine();
 		lineCount++;
 	}
 
 //TODO: wc is much faster but not portable
 	/*	QElapsedTimer myTimer;
 		myTimer.start();
 		QProcess wc;
 		wc.start(QString("wc"), QStringList() << "-l" << fileName);
 		size_t lineCount = 0;
 		while (wc.waitForReadyRead())
 			lineCount = wc.readLine().split(' ')[0].toInt();
 		lineCount++;	// last line not counted
 		DEBUG(" Elapsed time counting lines : " << myTimer.elapsed() << " ms");
 	*/
 	return lineCount;
 }
 
 /*!
   returns the number of lines in the device \c device and 0 if sequential.
   resets the position to 0!
 */
 size_t AsciiFilter::lineNumber(QIODevice &device) {
 	if (device.isSequential())
 		return 0;
 	if (!device.canReadLine())
 		DEBUG("WARNING in AsciiFilter::lineNumber(): device cannot 'readLine()' but using it anyway.");
 
 	size_t lineCount = 0;
 	device.seek(0);
 	while (!device.atEnd()) {
 		device.readLine();
 		lineCount++;
 	}
 	device.seek(0);
 
 	return lineCount;
 }
 
 void AsciiFilter::setCommentCharacter(const QString& s) {
 	d->commentCharacter = s;
 }
 QString AsciiFilter::commentCharacter() const {
 	return d->commentCharacter;
 }
 
 void AsciiFilter::setSeparatingCharacter(const QString& s) {
 	d->separatingCharacter = s;
 }
 QString AsciiFilter::separatingCharacter() const {
 	return d->separatingCharacter;
 }
 
 void AsciiFilter::setDateTimeFormat(const QString &f) {
 	d->dateTimeFormat = f;
 }
 QString AsciiFilter::dateTimeFormat() const {
 	return d->dateTimeFormat;
 }
 
 void AsciiFilter::setNumberFormat(QLocale::Language lang) {
 	d->numberFormat = lang;
 }
 QLocale::Language AsciiFilter::numberFormat() const {
 	return d->numberFormat;
 }
 
 void AsciiFilter::setAutoModeEnabled(const bool b) {
 	d->autoModeEnabled = b;
 }
 bool AsciiFilter::isAutoModeEnabled() const {
 	return d->autoModeEnabled;
 }
 
 void AsciiFilter::setHeaderEnabled(const bool b) {
 	d->headerEnabled = b;
 }
 bool AsciiFilter::isHeaderEnabled() const {
 	return d->headerEnabled;
 }
 
 void AsciiFilter::setSkipEmptyParts(const bool b) {
 	d->skipEmptyParts = b;
 }
 bool AsciiFilter::skipEmptyParts() const {
 	return d->skipEmptyParts;
 }
 
 void AsciiFilter::setCreateIndexEnabled(bool b) {
 	d->createIndexEnabled = b;
 }
 
 bool AsciiFilter::createIndexEnabled() const{
 	return d->createIndexEnabled;
 }
 
 void AsciiFilter::setSimplifyWhitespacesEnabled(bool b) {
 	d->simplifyWhitespacesEnabled = b;
 }
 bool AsciiFilter::simplifyWhitespacesEnabled() const {
 	return d->simplifyWhitespacesEnabled;
 }
 
 void AsciiFilter::setNaNValueToZero(bool b) {
 	if (b)
 		d->nanValue = 0;
 	else
 		d->nanValue = NAN;
 }
 bool AsciiFilter::NaNValueToZeroEnabled() const {
 	if (d->nanValue == 0)
 		return true;
 	return false;
 }
 
 void AsciiFilter::setRemoveQuotesEnabled(bool b) {
 	d->removeQuotesEnabled = b;
 }
 bool AsciiFilter::removeQuotesEnabled() const {
 	return d->removeQuotesEnabled;
 }
 
 void AsciiFilter::setVectorNames(const QString& s) {
 	d->vectorNames.clear();
 	if (!s.simplified().isEmpty())
 		d->vectorNames = s.simplified().split(' ');
 }
 QStringList AsciiFilter::vectorNames() const {
 	return d->vectorNames;
 }
 
 QVector<AbstractColumn::ColumnMode> AsciiFilter::columnModes() {
 	return d->columnModes;
 }
 
 void AsciiFilter::setStartRow(const int r) {
 	d->startRow = r;
 }
 int AsciiFilter::startRow() const {
 	return d->startRow;
 }
 
 void AsciiFilter::setEndRow(const int r) {
 	d->endRow = r;
 }
 int AsciiFilter::endRow() const {
 	return d->endRow;
 }
 
 void AsciiFilter::setStartColumn(const int c) {
 	d->startColumn = c;
 }
 int AsciiFilter::startColumn() const {
 	return d->startColumn;
 }
 
 void AsciiFilter::setEndColumn(const int c) {
 	d->endColumn = c;
 }
 int AsciiFilter::endColumn() const {
 	return d->endColumn;
 }
 
 //#####################################################################
 //################### Private implementation ##########################
 //#####################################################################
 AsciiFilterPrivate::AsciiFilterPrivate(AsciiFilter* owner) : q(owner),
 	commentCharacter("#"),
 	separatingCharacter("auto"),
 	numberFormat(QLocale::C),
 	autoModeEnabled(true),
 	headerEnabled(true),
 	skipEmptyParts(false),
 	simplifyWhitespacesEnabled(true),
 	nanValue(NAN),
 	removeQuotesEnabled(false),
 	createIndexEnabled(false),
 	startRow(1),
 	endRow(-1),
 	startColumn(1),
 	endColumn(-1),
 	mqttPreviewFirstEmptyColCount (0),
 	m_actualStartRow(1),
 	m_actualRows(0),
 	m_actualCols(0),
 	m_prepared(false),	
 	m_columnOffset(0) {
 }
 
 /*!
  * get a single line from device
  */
 QStringList AsciiFilterPrivate::getLineString(QIODevice& device) {
 	QString line;
 	do {	// skip comment lines in data lines
 		if (!device.canReadLine())
 			DEBUG("WARNING in AsciiFilterPrivate::getLineString(): device cannot 'readLine()' but using it anyway.");
 //			line = device.readAll();
 		line = device.readLine();
 	} while (line.startsWith(commentCharacter));
 
 	line.remove(QRegExp("[\\n\\r]"));	// remove any newline
 	if (simplifyWhitespacesEnabled)
 		line = line.simplified();
 	DEBUG("data line : \'" << line.toStdString() << '\'');
 	QStringList lineStringList = line.split(m_separator, (QString::SplitBehavior)skipEmptyParts);
 	//TODO: remove quotes here?
 	QDEBUG("data line, parsed: " << lineStringList);
 
 	return lineStringList;
 }
 
 /*!
  * returns -1 if the device couldn't be opened, 1 if the current read position in the device is at the end and 0 otherwise.
  */
 int AsciiFilterPrivate::prepareDeviceToRead(QIODevice& device) {
 	DEBUG("AsciiFilterPrivate::prepareDeviceToRead(): is sequential = " << device.isSequential() << ", can readLine = " << device.canReadLine());
 
     if (!device.open(QIODevice::ReadOnly))
 		return -1;
 
 	if (device.atEnd() && !device.isSequential()) // empty file
 		return 1;
 
 /////////////////////////////////////////////////////////////////
 	// Find first data line (ignoring comment lines)
 	DEBUG("	Skipping " << startRow - 1 << " lines");
 	for (int i = 0; i < startRow - 1; ++i) {
 		QString line;
 		if (!device.canReadLine())
 			DEBUG("WARNING in AsciiFilterPrivate::prepareDeviceToRead(): device cannot 'readLine()' but using it anyway.");
 		line = device.readLine();
 		DEBUG("	line = " << line.toStdString());
 
 		if (device.atEnd()) {
 			if (device.isSequential())
 				break;
 			else
 				return 1;
 		}
 	}
 
 	// Parse the first line:
 	// Determine the number of columns, create the columns and use (if selected) the first row to name them
 	QString firstLine;
 	do {	// skip comment lines
 		if (!device.canReadLine())
 			DEBUG("WARNING in AsciiFilterPrivate::prepareDeviceToRead(): device cannot 'readLine()' but using it anyway.");
 
 		if (device.atEnd()) {
 			DEBUG("device at end! Giving up.");
 			if (device.isSequential())
 				break;
 			else
 				return 1;
 		}
 
 		firstLine = device.readLine();
 	} while (firstLine.startsWith(commentCharacter));
 
 	DEBUG(" device position after first line and comments = " << device.pos());
 	firstLine.remove(QRegExp("[\\n\\r]"));	// remove any newline
 	if (simplifyWhitespacesEnabled)
 		firstLine = firstLine.simplified();
 	DEBUG("First line: \'" << firstLine.toStdString() << '\'');
 
 	// determine separator and split first line
 	QStringList firstLineStringList;
 	if (separatingCharacter == "auto") {
 		DEBUG("automatic separator");
 		QRegExp regExp("(\\s+)|(,\\s+)|(;\\s+)|(:\\s+)");
 		firstLineStringList = firstLine.split(regExp, (QString::SplitBehavior)skipEmptyParts);
 
 		if (!firstLineStringList.isEmpty()) {
 			int length1 = firstLineStringList.at(0).length();
 			if (firstLineStringList.size() > 1) {
 				int pos2 = firstLine.indexOf(firstLineStringList.at(1), length1);
 				m_separator = firstLine.mid(length1, pos2 - length1);
 			} else {
 				//old: separator = line.right(line.length() - length1);
 				m_separator = ' ';
 			}
 		}
 	} else {	// use given separator
 		// replace symbolic "TAB" with '\t'
 		m_separator = separatingCharacter.replace(QLatin1String("2xTAB"), "\t\t", Qt::CaseInsensitive);
 		m_separator = separatingCharacter.replace(QLatin1String("TAB"), "\t", Qt::CaseInsensitive);
 		// replace symbolic "SPACE" with ' '
 		m_separator = m_separator.replace(QLatin1String("2xSPACE"), QLatin1String("  "), Qt::CaseInsensitive);
 		m_separator = m_separator.replace(QLatin1String("3xSPACE"), QLatin1String("   "), Qt::CaseInsensitive);
 		m_separator = m_separator.replace(QLatin1String("4xSPACE"), QLatin1String("    "), Qt::CaseInsensitive);
 		m_separator = m_separator.replace(QLatin1String("SPACE"), QLatin1String(" "), Qt::CaseInsensitive);
 		firstLineStringList = firstLine.split(m_separator, (QString::SplitBehavior)skipEmptyParts);
 	}
 	DEBUG("separator: \'" << m_separator.toStdString() << '\'');
 	DEBUG("number of columns: " << firstLineStringList.size());
 	QDEBUG("first line: " << firstLineStringList);
 	DEBUG("headerEnabled: " << headerEnabled);
 
 	//optionally, remove potential spaces in the first line
 	if (simplifyWhitespacesEnabled) {
 		for (int i = 0; i < firstLineStringList.size(); ++i)
 			firstLineStringList[i] = firstLineStringList[i].simplified();
 	}
 
 	if (headerEnabled) {	// use first line to name vectors
 		vectorNames = firstLineStringList;
 		QDEBUG("vector names =" << vectorNames);
 		m_actualStartRow = startRow + 1;
 	} else
 		m_actualStartRow = startRow;
 
 	// set range to read
 	if (endColumn == -1) {
 		if (headerEnabled || vectorNames.size() == 0)
 			endColumn = firstLineStringList.size(); // last column
 		else
 			//number of vector names provided in the import dialog (not more than the maximal number of columns in the file)
 			endColumn = qMin(vectorNames.size(), firstLineStringList.size());
 	}
 	if (createIndexEnabled) {
 		vectorNames.prepend(i18n("Index"));
 		endColumn++;
 	}
 	m_actualCols = endColumn - startColumn + 1;
 
 //TEST: readline-seek-readline fails
 	/*	qint64 testpos = device.pos();
 		DEBUG("read data line @ pos " << testpos << " : " << device.readLine().toStdString());
 		device.seek(testpos);
 		testpos = device.pos();
 		DEBUG("read data line again @ pos " << testpos << "  : " << device.readLine().toStdString());
 	*/
 /////////////////////////////////////////////////////////////////
 
 	// parse first data line to determine data type for each column
 	if (!device.isSequential())
 		firstLineStringList = getLineString(device);
 
 	columnModes.resize(m_actualCols);
 	int col = 0;
 	if (createIndexEnabled) {
 		columnModes[0] = AbstractColumn::Integer;
 		col = 1;
 	}
 
 	for (auto& valueString : firstLineStringList) { // parse columns available in first data line
 		if (simplifyWhitespacesEnabled)
 			valueString = valueString.simplified();
 		if (col == m_actualCols)
 			break;
 		columnModes[col++] = AbstractFileFilter::columnMode(valueString, dateTimeFormat, numberFormat);
 	}
 	// parsing more lines to better determine data types
 	for (unsigned int i = 0; i < m_dataTypeLines; ++i) {
 		if (device.atEnd())	// EOF reached
 			break;
 		firstLineStringList = getLineString(device);
 
 		createIndexEnabled ? col = 1 : col = 0;
 
 		for (auto& valueString : firstLineStringList) {
 			if (simplifyWhitespacesEnabled)
 				valueString = valueString.simplified();
 			if (col == m_actualCols)
 				break;
 			AbstractColumn::ColumnMode mode = AbstractFileFilter::columnMode(valueString, dateTimeFormat, numberFormat);
 
 			// numeric: integer -> numeric
 			if (mode == AbstractColumn::Numeric && columnModes[col] == AbstractColumn::Integer)
 				columnModes[col] = mode;
 			// text: non text -> text
 			if (mode == AbstractColumn::Text && columnModes[col] != AbstractColumn::Text)
 				columnModes[col] = mode;
 
 			col++;
 		}
 	}
 	QDEBUG("column modes = " << columnModes);
 
 	// ATTENTION: This resets the position in the device to 0
 	m_actualRows = (int)AsciiFilter::lineNumber(device);
 
 	const int actualEndRow = (endRow == -1 || endRow > m_actualRows) ? m_actualRows : endRow;
 	m_actualRows = actualEndRow - m_actualStartRow + 1;
 
 	DEBUG("start/end column: " << startColumn << ' ' << endColumn);
 	DEBUG("start/end row: " << m_actualStartRow << ' ' << actualEndRow);
 	DEBUG("actual cols/rows (w/o header): " << m_actualCols << ' ' << m_actualRows);
 
 	if (m_actualRows == 0 && !device.isSequential())
 		return 1;
 
 	return 0;
 }
 
 /*!
     reads the content of the file \c fileName to the data source \c dataSource. Uses the settings defined in the data source.
 */
 void AsciiFilterPrivate::readDataFromFile(const QString& fileName, AbstractDataSource* dataSource, AbstractFileFilter::ImportMode importMode) {
 	DEBUG("AsciiFilterPrivate::readDataFromFile(): fileName = \'" << fileName.toStdString() << "\', dataSource = "
 	      << dataSource << ", mode = " << ENUM_TO_STRING(AbstractFileFilter, ImportMode, importMode));
 
 	KFilterDev device(fileName);
 	readDataFromDevice(device, dataSource, importMode);
 }
 
 qint64 AsciiFilterPrivate::readFromLiveDevice(QIODevice& device, AbstractDataSource* dataSource, qint64 from) {
 	DEBUG("AsciiFilterPrivate::readFromLiveDevice(): bytes available = " << device.bytesAvailable() << ", from = " << from);
 	if (device.bytesAvailable() <= 0) {
 		DEBUG("	No new data available");
 		return 0;
 	}
 
 	//TODO: may be also a matrix?
 	auto* spreadsheet = dynamic_cast<LiveDataSource*>(dataSource);
 
 	if (spreadsheet->sourceType() != LiveDataSource::SourceType::FileOrPipe)
 		if (device.isSequential() && device.bytesAvailable() < (int)sizeof(quint16))
 			return 0;
 
 	if (!m_prepared) {
 		DEBUG("	Preparing ..");
 
 		switch (spreadsheet->sourceType()) {
 		case LiveDataSource::SourceType::FileOrPipe: {
 			const int deviceError = prepareDeviceToRead(device);
 			if (deviceError != 0) {
 				DEBUG("	Device error = " << deviceError);
 				return 0;
 			}
 			break;
 		}
 		case LiveDataSource::SourceType::NetworkTcpSocket:
 		case LiveDataSource::SourceType::NetworkUdpSocket:
 		case LiveDataSource::SourceType::LocalSocket:
 		case LiveDataSource::SourceType::SerialPort:
 			m_actualRows = 1;
 			if (createIndexEnabled) {
 				m_actualCols = 2;
 				columnModes << AbstractColumn::Integer << AbstractColumn::Numeric;
 				vectorNames << i18n("Index") << i18n("Value");
 			} else {
 				m_actualCols = 1;
 				columnModes << AbstractColumn::Numeric;
 				vectorNames << i18n("Value");
 			}
 			QDEBUG("	vector names = " << vectorNames);
 		case LiveDataSource::SourceType::MQTT:
 			break;
 		}
 
 		// prepare import for spreadsheet
 		spreadsheet->setUndoAware(false);
 		spreadsheet->resize(AbstractFileFilter::Replace, vectorNames, m_actualCols);
 		DEBUG("	data source resized to col: " << m_actualCols);
 		DEBUG("	data source rowCount: " << spreadsheet->rowCount());
 
 		//columns in a file data source don't have any manual changes.
 		//make the available columns undo unaware and suppress the "data changed" signal.
 		//data changes will be propagated via an explicit Column::setChanged() call once new data was read.
 		for (int i = 0; i < spreadsheet->childCount<Column>(); i++) {
 			spreadsheet->child<Column>(i)->setUndoAware(false);
 			spreadsheet->child<Column>(i)->setSuppressDataChangedSignal(true);
 		}
 
 		int keepNValues = spreadsheet->keepNValues();
 		if (keepNValues == 0)
 			spreadsheet->setRowCount(m_actualRows > 1 ? m_actualRows : 1);
 		else {
 			spreadsheet->setRowCount(keepNValues);
 			m_actualRows = keepNValues;
 		}
 
 		m_dataContainer.resize(m_actualCols);
 
 		DEBUG("	Setting data ..");
 		for (int n = 0; n < m_actualCols; ++n) {
 			// data() returns a void* which is a pointer to any data type (see ColumnPrivate.cpp)
 			spreadsheet->child<Column>(n)->setColumnMode(columnModes[n]);
 			switch (columnModes[n]) {
 			case AbstractColumn::Numeric: {
 				QVector<double>* vector = static_cast<QVector<double>* >(spreadsheet->child<Column>(n)->data());
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 			case AbstractColumn::Integer: {
 				QVector<int>* vector = static_cast<QVector<int>* >(spreadsheet->child<Column>(n)->data());
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 			case AbstractColumn::Text: {
 				QVector<QString>* vector = static_cast<QVector<QString>*>(spreadsheet->child<Column>(n)->data());
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 			case AbstractColumn::DateTime: {
 				QVector<QDateTime>* vector = static_cast<QVector<QDateTime>* >(spreadsheet->child<Column>(n)->data());
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 			//TODO
 			case AbstractColumn::Month:
 			case AbstractColumn::Day:
 				break;
 			}
 		}
 
 		DEBUG("	Prepared!");
 	}
 
 	qint64 bytesread = 0;
 
 #ifdef PERFTRACE_LIVE_IMPORT
 	PERFTRACE("AsciiLiveDataImportTotal: ");
 #endif
 	LiveDataSource::ReadingType readingType;
 	if (!m_prepared) {
 		readingType = LiveDataSource::ReadingType::TillEnd;
 	} else {
 		//we have to read all the data when reading from end
 		//so we set readingType to TillEnd
 		if (spreadsheet->readingType() == LiveDataSource::ReadingType::FromEnd)
 			readingType = LiveDataSource::ReadingType::TillEnd;
 		//if we read the whole file we just start from the beginning of it
 		//and read till end
 		else if (spreadsheet->readingType() == LiveDataSource::ReadingType::WholeFile)
 			readingType = LiveDataSource::ReadingType::TillEnd;
 		else
 			readingType = spreadsheet->readingType();
 	}
 	DEBUG("	Reading type = " << ENUM_TO_STRING(LiveDataSource, ReadingType, readingType));
 
 	//move to the last read position, from == total bytes read
 	//since the other source types are sequential we cannot seek on them
 	if (spreadsheet->sourceType() == LiveDataSource::SourceType::FileOrPipe)
 		device.seek(from);
 
 	//count the new lines, increase actualrows on each
 	//now we read all the new lines, if we want to use sample rate
 	//then here we can do it, if we have actually sample rate number of lines :-?
 	int newLinesForSampleSizeNotTillEnd = 0;
 	int newLinesTillEnd = 0;
 	QVector<QString> newData;
 	if (readingType != LiveDataSource::ReadingType::TillEnd)
 		newData.resize(spreadsheet->sampleSize());
 
 	int newDataIdx = 0;
 	{
 #ifdef PERFTRACE_LIVE_IMPORT
 		PERFTRACE("AsciiLiveDataImportReadingFromFile: ");
 #endif
 		DEBUG("	source type = " << ENUM_TO_STRING(LiveDataSource, SourceType, spreadsheet->sourceType()));
 		while (!device.atEnd()) {
 			if (readingType != LiveDataSource::ReadingType::TillEnd) {
 				switch (spreadsheet->sourceType()) {	// different sources need different read methods
 				case LiveDataSource::SourceType::LocalSocket:
 					newData[newDataIdx++] = device.readAll();
 					break;
 				case LiveDataSource::SourceType::NetworkUdpSocket:
 					newData[newDataIdx++] = device.read(device.bytesAvailable());
 					break;
 				case LiveDataSource::SourceType::FileOrPipe:
 					newData.push_back(device.readLine());
 					break;
 				case LiveDataSource::SourceType::NetworkTcpSocket:
 				//TODO: check serial port
 				case LiveDataSource::SourceType::SerialPort:
 					newData[newDataIdx++] = device.read(device.bytesAvailable());
 				case LiveDataSource::SourceType::MQTT:
 					break;
 				}
 			} else {	// ReadingType::TillEnd
 				switch (spreadsheet->sourceType()) {	// different sources need different read methods
 				case LiveDataSource::SourceType::LocalSocket:
 					newData.push_back(device.readAll());
 					break;
 				case LiveDataSource::SourceType::NetworkUdpSocket:
 					newData.push_back(device.read(device.bytesAvailable()));
 					break;
 				case LiveDataSource::SourceType::FileOrPipe:
 					newData.push_back(device.readLine());
 					break;
 				case LiveDataSource::SourceType::NetworkTcpSocket:
 				//TODO: check serial port
 				case LiveDataSource::SourceType::SerialPort:
 					newData.push_back(device.read(device.bytesAvailable()));
 				case LiveDataSource::SourceType::MQTT:
 					break;
 				}
 			}
 			newLinesTillEnd++;
 
 			if (readingType != LiveDataSource::ReadingType::TillEnd) {
 				newLinesForSampleSizeNotTillEnd++;
 				//for Continuous reading and FromEnd we read sample rate number of lines if possible
 				//here TillEnd and Whole file behave the same
 				if (newLinesForSampleSizeNotTillEnd == spreadsheet->sampleSize())
 					break;
 			}
 		}
 		QDEBUG("	data read: " << newData);
 	}
 	//now we reset the readingType
 	if (spreadsheet->readingType() == LiveDataSource::ReadingType::FromEnd)
 		readingType = spreadsheet->readingType();
 
 	//we had less new lines than the sample size specified
 	if (readingType != LiveDataSource::ReadingType::TillEnd)
 		QDEBUG("	Removed empty lines: " << newData.removeAll(""));
 
 	//back to the last read position before counting when reading from files
 	if (spreadsheet->sourceType() == LiveDataSource::SourceType::FileOrPipe)
 		device.seek(from);
 
 	const int spreadsheetRowCountBeforeResize = spreadsheet->rowCount();
 
 	int currentRow = 0; // indexes the position in the vector(column)
 	int linesToRead = 0;
 	int keepNValues = spreadsheet->keepNValues();
 
 	DEBUG("	Increase row count. keepNValues = " << keepNValues);
 	if (m_prepared) {
 		//increase row count if we don't have a fixed size
 		//but only after the preparation step
 		if (keepNValues == 0) {
 			DEBUG("	keep All values");
 			if (readingType != LiveDataSource::ReadingType::TillEnd)
 				m_actualRows += qMin(newData.size(), spreadsheet->sampleSize());
 			else {
 				//we don't increase it if we reread the whole file, we reset it
 				if (!(spreadsheet->readingType() == LiveDataSource::ReadingType::WholeFile))
 					m_actualRows += newData.size();
 				else
 					m_actualRows = newData.size();
 			}
 
 			//appending
 			if (spreadsheet->readingType() == LiveDataSource::ReadingType::WholeFile)
 				linesToRead = m_actualRows;
 			else
 				linesToRead = m_actualRows - spreadsheetRowCountBeforeResize;
 		} else {	// fixed size
 			DEBUG("	keep " << keepNValues << " values");
 			if (readingType == LiveDataSource::ReadingType::TillEnd) {
 				//we had more lines than the fixed size, so we read m_actualRows number of lines
 				if (newLinesTillEnd > m_actualRows) {
 					linesToRead = m_actualRows;
 					//TODO after reading we should skip the next data lines
 					//because it's TillEnd actually
 				} else
 					linesToRead = newLinesTillEnd;
 			} else {
 				//we read max sample size number of lines when the reading mode
 				//is ContinuouslyFixed or FromEnd, WholeFile is disabled
 				linesToRead = qMin(spreadsheet->sampleSize(), newLinesTillEnd);
 			}
 		}
 		DEBUG("	actual rows = " << m_actualRows);
 
 		if (linesToRead == 0)
 			return 0;
 	} else {	// not prepared
 		linesToRead = newLinesTillEnd;
 		if (headerEnabled)
 			--m_actualRows;
 	}
 	DEBUG("	lines to read = " << linesToRead);
 
 	if (spreadsheet->sourceType() == LiveDataSource::SourceType::FileOrPipe || spreadsheet->sourceType() == LiveDataSource::SourceType::NetworkUdpSocket) {
 		if (m_actualRows < linesToRead) {
 			DEBUG("	SET lines to read to " << m_actualRows);
 			linesToRead = m_actualRows;
 		}
 	}
 
 	//new rows/resize columns if we don't have a fixed size
 	//TODO if the user changes this value..m_resizedToFixedSize..setResizedToFixedSize
 	if (keepNValues == 0) {
 #ifdef PERFTRACE_LIVE_IMPORT
 		PERFTRACE("AsciiLiveDataImportResizing: ");
 #endif
 		if (spreadsheet->rowCount() < m_actualRows)
 			spreadsheet->setRowCount(m_actualRows);
 
 		if (!m_prepared)
 			currentRow = 0;
 		else {
 			// indexes the position in the vector(column)
 			if (spreadsheet->readingType() == LiveDataSource::ReadingType::WholeFile)
 				currentRow = 0;
 			else
 				currentRow = spreadsheetRowCountBeforeResize;
 		}
 
 		// if we have fixed size, we do this only once in preparation, here we can use
 		// m_prepared and we need something to decide whether it has a fixed size or increasing
 		for (int n = 0; n < m_actualCols; ++n) {
 			// data() returns a void* which is a pointer to any data type (see ColumnPrivate.cpp)
 			switch (columnModes[n]) {
 			case AbstractColumn::Numeric: {
 				QVector<double>* vector = static_cast<QVector<double>* >(spreadsheet->child<Column>(n)->data());
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 			case AbstractColumn::Integer: {
 				QVector<int>* vector = static_cast<QVector<int>* >(spreadsheet->child<Column>(n)->data());
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 			case AbstractColumn::Text: {
 				QVector<QString>* vector = static_cast<QVector<QString>*>(spreadsheet->child<Column>(n)->data());
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 			case AbstractColumn::DateTime: {
 				QVector<QDateTime>* vector = static_cast<QVector<QDateTime>* >(spreadsheet->child<Column>(n)->data());
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 			//TODO
 			case AbstractColumn::Month:
 			case AbstractColumn::Day:
 				break;
 			}
 		}
 	} else {	// fixed size
 		//when we have a fixed size we have to pop sampleSize number of lines if specified
 		//here popping, setting currentRow
 		if (!m_prepared) {
 			if (spreadsheet->readingType() == LiveDataSource::ReadingType::WholeFile)
 				currentRow = 0;
 			else
 				currentRow = m_actualRows - qMin(newLinesTillEnd, m_actualRows);
 		} else {
 			if (readingType == LiveDataSource::ReadingType::TillEnd) {
 				if (newLinesTillEnd > m_actualRows) {
 					currentRow = 0;
 				} else {
 					if (spreadsheet->readingType() == LiveDataSource::ReadingType::WholeFile)
 						currentRow = 0;
 					else
 						currentRow = m_actualRows - newLinesTillEnd;
 				}
 			} else {
 				//we read max sample size number of lines when the reading mode
 				//is ContinuouslyFixed or FromEnd
 				currentRow = m_actualRows - qMin(spreadsheet->sampleSize(), newLinesTillEnd);
 			}
 		}
 
 		if (m_prepared) {
 #ifdef PERFTRACE_LIVE_IMPORT
 			PERFTRACE("AsciiLiveDataImportPopping: ");
 #endif
 			// enable data change signal
 			for (int col = 0; col < m_actualCols; ++col)
 				spreadsheet->child<Column>(col)->setSuppressDataChangedSignal(false);
 
 			for (int row = 0; row < linesToRead; ++row) {
 				for (int col = 0; col < m_actualCols; ++col) {
 					switch (columnModes[col]) {
 					case AbstractColumn::Numeric: {
 						QVector<double>* vector = static_cast<QVector<double>* >(spreadsheet->child<Column>(col)->data());
 						vector->pop_front();
 						vector->resize(m_actualRows);
 						m_dataContainer[col] = static_cast<void *>(vector);
 						break;
 					}
 					case AbstractColumn::Integer: {
 						QVector<int>* vector = static_cast<QVector<int>* >(spreadsheet->child<Column>(col)->data());
 						vector->pop_front();
 						vector->resize(m_actualRows);
 						m_dataContainer[col] = static_cast<void *>(vector);
 						break;
 					}
 					case AbstractColumn::Text: {
 						QVector<QString>* vector = static_cast<QVector<QString>*>(spreadsheet->child<Column>(col)->data());
 						vector->pop_front();
 						vector->resize(m_actualRows);
 						m_dataContainer[col] = static_cast<void *>(vector);
 						break;
 					}
 					case AbstractColumn::DateTime: {
 						QVector<QDateTime>* vector = static_cast<QVector<QDateTime>* >(spreadsheet->child<Column>(col)->data());
 						vector->pop_front();
 						vector->resize(m_actualRows);
 						m_dataContainer[col] = static_cast<void *>(vector);
 						break;
 					}
 					//TODO
 					case AbstractColumn::Month:
 					case AbstractColumn::Day:
 						break;
 					}
 				}
 			}
 		}
 	}
 
 	// from the last row we read the new data in the spreadsheet
 	DEBUG("	Reading from line "  << currentRow << " till end line " << newLinesTillEnd);
 	DEBUG("	Lines to read:" << linesToRead <<", actual rows:" << m_actualRows << ", actual cols:" << m_actualCols);
 	newDataIdx = 0;
 	if (readingType == LiveDataSource::ReadingType::FromEnd) {
 		if (m_prepared) {
 			if (newData.size() > spreadsheet->sampleSize())
 				newDataIdx = newData.size() - spreadsheet->sampleSize();
 			//since we skip a couple of lines, we need to count those bytes too
 			for (int i = 0; i < newDataIdx; ++i)
 				bytesread += newData.at(i).size();
 		}
 	}
 	DEBUG("	newDataIdx: " << newDataIdx);
 
 	static int indexColumnIdx = 1;
 	{
 #ifdef PERFTRACE_LIVE_IMPORT
 		PERFTRACE("AsciiLiveDataImportFillingContainers: ");
 #endif
 		int row = 0;
 
 		if (readingType == LiveDataSource::ReadingType::TillEnd || (readingType == LiveDataSource::ReadingType::ContinuousFixed)) {
 			if (headerEnabled) {
 				if (!m_prepared) {
 					row = 1;
 					bytesread += newData.at(0).size();
 				}
 			}
 		}
 		if (spreadsheet->sourceType() == LiveDataSource::SourceType::FileOrPipe) {
 			if (readingType == LiveDataSource::ReadingType::WholeFile) {
 				if (headerEnabled) {
 					row = 1;
 					bytesread += newData.at(0).size();
 				}
 			}
 		}
 
 		for (; row < linesToRead; ++row) {
 			DEBUG("\n	Reading row " << row + 1 << " of " << linesToRead);
 			QString line;
 			if (readingType == LiveDataSource::ReadingType::FromEnd)
 				line = newData.at(newDataIdx++);
 			else
 				line = newData.at(row);
 			//when we read the whole file we don't care about the previous position
 			//so we don't have to count those bytes
 			if (readingType != LiveDataSource::ReadingType::WholeFile) {
 				if (spreadsheet->sourceType() == LiveDataSource::SourceType::FileOrPipe) {
 					bytesread += line.size();
 				}
 			}
 
 			DEBUG("	Line bytes: " << line.size() << " line: " << line.toStdString());
 			if (simplifyWhitespacesEnabled)
 				line = line.simplified();
 
 			if (line.isEmpty() || line.startsWith(commentCharacter)) // skip empty or commented lines
 				continue;
 
 			QLocale locale(numberFormat);
 
 			QStringList lineStringList;
 			// only FileOrPipe support multiple columns
 			if (spreadsheet->sourceType() == LiveDataSource::SourceType::FileOrPipe)
 				lineStringList = line.split(m_separator, (QString::SplitBehavior)skipEmptyParts);
 			else
 				lineStringList << line;
 			QDEBUG("	line = " << lineStringList << ", separator = \'" << m_separator << "\'");
 
 			if (createIndexEnabled) {
 				if (spreadsheet->keepNValues() == 0)
 					lineStringList.prepend(QString::number(currentRow + 1));
 				else
 					lineStringList.prepend(QString::number(indexColumnIdx++));
 			}
 
 			QDEBUG("	column modes = " << columnModes);
 			for (int n = 0; n < m_actualCols; ++n) {
 				DEBUG("	actual col = " << n);
 				if (n < lineStringList.size()) {
 					QString valueString = lineStringList.at(n);
 					DEBUG("	value string = " << valueString.toStdString());
 
 					// set value depending on data type
 					switch (columnModes[n]) {
 					case AbstractColumn::Numeric: {
 						DEBUG("	Numeric");
 						bool isNumber;
 						const double value = locale.toDouble(valueString, &isNumber);
 						static_cast<QVector<double>*>(m_dataContainer[n])->operator[](currentRow) = (isNumber ? value : nanValue);
 						qDebug() << "dataContainer[" << n << "] size:" << static_cast<QVector<double>*>(m_dataContainer[n])->size();
 						break;
 					}
 					case AbstractColumn::Integer: {
 						DEBUG("	Integer");
 						bool isNumber;
 						const int value = locale.toInt(valueString, &isNumber);
 						DEBUG("	container size = " << m_dataContainer.size() << ", current row = " << currentRow);
 						static_cast<QVector<int>*>(m_dataContainer[n])->operator[](currentRow) = (isNumber ? value : 0);
 						qDebug() << "dataContainer[" << n << "] size:" << static_cast<QVector<int>*>(m_dataContainer[n])->size();
 
 						break;
 					}
 					case AbstractColumn::DateTime: {
 						const QDateTime valueDateTime = QDateTime::fromString(valueString, dateTimeFormat);
 						static_cast<QVector<QDateTime>*>(m_dataContainer[n])->operator[](currentRow) = valueDateTime.isValid() ? valueDateTime : QDateTime();
 						break;
 					}
 					case AbstractColumn::Text:
 						if (removeQuotesEnabled)
 							valueString.remove(QRegExp("[\"\']"));
 						static_cast<QVector<QString>*>(m_dataContainer[n])->operator[](currentRow) = valueString;
 						break;
 					case AbstractColumn::Month:
 						//TODO
 						break;
 					case AbstractColumn::Day:
 						//TODO
 						break;
 					}
 				} else {
 					DEBUG("	missing columns in this line");
 					switch (columnModes[n]) {
 					case AbstractColumn::Numeric:
 						static_cast<QVector<double>*>(m_dataContainer[n])->operator[](currentRow) = nanValue;
 						break;
 					case AbstractColumn::Integer:
 						static_cast<QVector<int>*>(m_dataContainer[n])->operator[](currentRow) = 0;
 						break;
 					case AbstractColumn::DateTime:
 						static_cast<QVector<QDateTime>*>(m_dataContainer[n])->operator[](currentRow) = QDateTime();
 						break;
 					case AbstractColumn::Text:
 						static_cast<QVector<QString>*>(m_dataContainer[n])->operator[](currentRow) = "";
 						break;
 					case AbstractColumn::Month:
 						//TODO
 						break;
 					case AbstractColumn::Day:
 						//TODO
 						break;
 					}
 				}
 			}
 			currentRow++;
 		}
 	}
 
 	if (m_prepared) {
 		//notify all affected columns and plots about the changes
 		PERFTRACE("AsciiLiveDataImport, notify affected columns and plots");
 		const Project* project = spreadsheet->project();
 		QVector<const XYCurve*> curves = project->children<const XYCurve>(AbstractAspect::Recursive);
 		QVector<CartesianPlot*> plots;
 		for (int n = 0; n < m_actualCols; ++n) {
 			Column* column = spreadsheet->column(n);
 
 			//determine the plots where the column is consumed
 			for (const auto* curve : curves) {
 				if (curve->xColumn() == column || curve->yColumn() == column) {
 					auto* plot = dynamic_cast<CartesianPlot*>(curve->parentAspect());
 					if (plots.indexOf(plot) == -1) {
 						plots << plot;
 						plot->setSuppressDataChangedSignal(true);
 					}
 				}
 			}
 
 			column->setChanged();
 		}
 
 		//loop over all affected plots and retransform them
 		for (auto* plot : plots) {
 			plot->setSuppressDataChangedSignal(false);
 			plot->dataChanged();
 		}
 	}
 
 	m_prepared = true;
 
 	DEBUG("AsciiFilterPrivate::readFromLiveDevice() DONE");
 	return bytesread;
 }
 
 /*!
     reads the content of device \c device to the data source \c dataSource. Uses the settings defined in the data source.
 */
 void AsciiFilterPrivate::readDataFromDevice(QIODevice& device, AbstractDataSource* dataSource, AbstractFileFilter::ImportMode importMode, int lines) {
 	DEBUG("AsciiFilterPrivate::readDataFromDevice(): dataSource = " << dataSource
 	      << ", mode = " << ENUM_TO_STRING(AbstractFileFilter, ImportMode, importMode) << ", lines = " << lines);
 
 	if (!m_prepared) {
 		const int deviceError = prepareDeviceToRead(device);
 		if (deviceError != 0) {
 			DEBUG("Device error = " << deviceError);
 			return;
 		}
 
-		// matrix data has only one column mode (which is not text)
+		// matrix data has only one column mode
 		if (dynamic_cast<Matrix*>(dataSource)) {
 			auto mode = columnModes[0];
+			//TODO: remove this when Matrix supports text type
 			if (mode == AbstractColumn::Text)
 				mode = AbstractColumn::Numeric;
 			for (auto& c : columnModes)
 				if (c != mode)
 					c = mode;
 		}
 
 		m_columnOffset = dataSource->prepareImport(m_dataContainer, importMode, m_actualRows, m_actualCols, vectorNames, columnModes);
 		m_prepared = true;
 	}
 
 	DEBUG("locale = " << QLocale::languageToString(numberFormat).toStdString());
 	QLocale locale(numberFormat);
 
 	// Read the data
 	int currentRow = 0;	// indexes the position in the vector(column)
 	if (lines == -1)
 		lines = m_actualRows;
 
 	//skip data lines, if required
 	DEBUG("	Skipping " << m_actualStartRow - 1 << " lines");
 	for (int i = 0; i < m_actualStartRow - 1; ++i)
 		device.readLine();
 
 	DEBUG("	Reading " << qMin(lines, m_actualRows)  << " lines");
 	for (int i = 0; i < qMin(lines, m_actualRows); ++i) {
 		QString line = device.readLine();
 
 		line.remove(QRegExp("[\\n\\r]"));	// remove any newline
 		if (simplifyWhitespacesEnabled)
 			line = line.simplified();
 
 		if (line.isEmpty() || line.startsWith(commentCharacter)) // skip empty or commented lines
 			continue;
 
 		QStringList lineStringList = line.split(m_separator, (QString::SplitBehavior)skipEmptyParts);
 
 		// remove left white spaces
 		if (skipEmptyParts) {
 			for (int n = 0; n < lineStringList.size(); ++n) {
 				QString valueString = lineStringList.at(n);
 				if (!QString::compare(valueString, " ")) {
 					lineStringList.removeAt(n);
 					n--;
 				}
 			}
 		}
 
 		for (int n = 0; n < m_actualCols; ++n) {
 			// index column if required
 			if (n == 0 && createIndexEnabled) {
 				static_cast<QVector<int>*>(m_dataContainer[0])->operator[](currentRow) = i + 1;
 				continue;
 			}
 
 			if ((createIndexEnabled ? n - 1 : n) < lineStringList.size()) {
 				QString valueString = lineStringList.at(createIndexEnabled ? n - 1 : n);
 
 				// set value depending on data type
 				switch (columnModes[n]) {
 				case AbstractColumn::Numeric: {
 					bool isNumber;
 					const double value = locale.toDouble(valueString, &isNumber);
 					static_cast<QVector<double>*>(m_dataContainer[n])->operator[](currentRow) = (isNumber ? value : nanValue);
 					break;
 				}
 				case AbstractColumn::Integer: {
 					bool isNumber;
 					const int value = locale.toInt(valueString, &isNumber);
 					static_cast<QVector<int>*>(m_dataContainer[n])->operator[](currentRow) = (isNumber ? value : 0);
 					break;
 				}
 				case AbstractColumn::DateTime: {
 					const QDateTime valueDateTime = QDateTime::fromString(valueString, dateTimeFormat);
 					static_cast<QVector<QDateTime>*>(m_dataContainer[n])->operator[](currentRow) = valueDateTime.isValid() ? valueDateTime : QDateTime();
 					break;
 				}
-				case AbstractColumn::Text:
+				case AbstractColumn::Text: {
 					if (removeQuotesEnabled)
 						valueString.remove(QRegExp("[\"\']"));
-					static_cast<QVector<QString>*>(m_dataContainer[n])->operator[](currentRow) = valueString;
+					DEBUG("	set value (" << currentRow << ", " << n << "): " << valueString.toStdString());
+					QVector<QString>* colData = static_cast<QVector<QString>*>(m_dataContainer[n]);
+					//TODO: QString size is not defined. Can not preallocate data matrix!
+					//colData->operator[](currentRow) = valueString;
 					break;
+				}
 				case AbstractColumn::Month:	// never happens
 				case AbstractColumn::Day:
 					break;
 				}
 			} else {	// missing columns in this line
 				switch (columnModes[n]) {
 				case AbstractColumn::Numeric:
 					static_cast<QVector<double>*>(m_dataContainer[n])->operator[](currentRow) = nanValue;
 					break;
 				case AbstractColumn::Integer:
 					static_cast<QVector<int>*>(m_dataContainer[n])->operator[](currentRow) = 0;
 					break;
 				case AbstractColumn::DateTime:
 					static_cast<QVector<QDateTime>*>(m_dataContainer[n])->operator[](currentRow) = QDateTime();
 					break;
 				case AbstractColumn::Text:
 					static_cast<QVector<QString>*>(m_dataContainer[n])->operator[](currentRow) = "";
 					break;
 				case AbstractColumn::Month:	// never happens
 				case AbstractColumn::Day:
 					break;
 				}
 			}
 		}
 
 		currentRow++;
 		emit q->completed(100 * currentRow/m_actualRows);
 	}
 	DEBUG("	Read " << currentRow << " lines");
 
 	dataSource->finalizeImport(m_columnOffset, startColumn, endColumn, currentRow, dateTimeFormat, importMode);
 }
 
 /*!
  * preview for special devices (local/UDP/TCP socket or serial port)
  */
 QVector<QStringList> AsciiFilterPrivate::preview(QIODevice &device) {
 	DEBUG("AsciiFilterPrivate::preview(): bytesAvailable = " << device.bytesAvailable() << ", isSequential = " << device.isSequential());
 	QVector<QStringList> dataStrings;
 
 	if (!(device.bytesAvailable() > 0)) {
 		DEBUG("No new data available");
 		return dataStrings;
 	}
 
 	if (device.isSequential() && device.bytesAvailable() < (int)sizeof(quint16))
 		return dataStrings;
 
 #ifdef PERFTRACE_LIVE_IMPORT
 	PERFTRACE("AsciiLiveDataImportTotal: ");
 #endif
 
 	int linesToRead = 0;
 	QVector<QString> newData;
 
 	//TODO: serial port "read(nBytes)"?
 	while (!device.atEnd()) {
 		if (device.canReadLine())
 			newData.push_back(device.readLine());
 		else	// UDP fails otherwise
 			newData.push_back(device.readAll());
 		linesToRead++;
 	}
 	QDEBUG("	data = " << newData);
 
 	if (linesToRead == 0) return dataStrings;
 
 	int col = 0;
 	int colMax = newData.at(0).size();
 	if (createIndexEnabled)
 		colMax++;
 	columnModes.resize(colMax);
 	if (createIndexEnabled) {
 		columnModes[0] = AbstractColumn::ColumnMode::Integer;
 		col = 1;
 		vectorNames.prepend(i18n("Index"));
 	}
 	vectorNames.append(i18n("Value"));
 	QDEBUG("	vector names = " << vectorNames);
 
 	for (const auto& valueString : newData.at(0).split(' ', QString::SkipEmptyParts)) {
 		if (col == colMax)
 			break;
 		columnModes[col++] = AbstractFileFilter::columnMode(valueString, dateTimeFormat, numberFormat);
 	}
 
 	for (int i = 0; i < linesToRead; ++i) {
 		QString line = newData.at(i);
 
 		if (simplifyWhitespacesEnabled)
 			line = line.simplified();
 
 		if (line.isEmpty() || line.startsWith(commentCharacter)) // skip empty or commented lines
 			continue;
 
 		QLocale locale(numberFormat);
 
 		QStringList lineStringList = line.split(' ', QString::SkipEmptyParts);
 		if (createIndexEnabled)
 			lineStringList.prepend(QString::number(i + 1));
 
 		QStringList lineString;
 		for (int n = 0; n < lineStringList.size(); ++n) {
 			if (n < lineStringList.size()) {
 				QString valueString = lineStringList.at(n);
 
 				switch (columnModes[n]) {
 				case AbstractColumn::Numeric: {
 					bool isNumber;
 					const double value = locale.toDouble(valueString, &isNumber);
 					lineString += QString::number(isNumber ? value : nanValue, 'g', 16);
 					break;
 				}
 				case AbstractColumn::Integer: {
 					bool isNumber;
 					const int value = locale.toInt(valueString, &isNumber);
 					lineString += QString::number(isNumber ? value : 0);
 					break;
 				}
 				case AbstractColumn::DateTime: {
 					const QDateTime valueDateTime = QDateTime::fromString(valueString, dateTimeFormat);
 					lineString += valueDateTime.isValid() ? valueDateTime.toString(dateTimeFormat) : QLatin1String(" ");
 					break;
 				}
 				case AbstractColumn::Text:
 					if (removeQuotesEnabled)
 						valueString.remove(QRegExp("[\"\']"));
 					lineString += valueString;
 					break;
 				case AbstractColumn::Month:	// never happens
 				case AbstractColumn::Day:
 					break;
 				}
 			} else 	// missing columns in this line
 				lineString += QLatin1String("");
 		}
 		dataStrings << lineString;
 	}
 
 	return dataStrings;
 }
 
 /*!
  * generates the preview for the file \c fileName reading the provided number of \c lines.
  */
 QVector<QStringList> AsciiFilterPrivate::preview(const QString& fileName, int lines) {
 	QVector<QStringList> dataStrings;
 
 	KFilterDev device(fileName);
 	const int deviceError = prepareDeviceToRead(device);
 	if (deviceError != 0) {
 		DEBUG("Device error = " << deviceError);
 		return dataStrings;
 	}
 
 	//number formatting
 	DEBUG("locale = " << QLocale::languageToString(numberFormat).toStdString());
 	QLocale locale(numberFormat);
 
 	// Read the data
 	if (lines == -1)
 		lines = m_actualRows;
 
 	// set column names for preview
 	if (!headerEnabled) {
 		int start = 0;
 		if (createIndexEnabled)
 			start = 1;
 		for (int i = start; i < m_actualCols; i++)
 				vectorNames << "Column " + QString::number(i + 1);
 	}
 	QDEBUG("	column names = " << vectorNames);
 
 	//skip data lines, if required
 	DEBUG("	Skipping " << m_actualStartRow - 1 << " lines");
 	for (int i = 0; i < m_actualStartRow - 1; ++i)
 		device.readLine();
 
 	DEBUG("	Generating preview for " << qMin(lines, m_actualRows)  << " lines");
 	for (int i = 0; i < qMin(lines, m_actualRows); ++i) {
 		QString line = device.readLine();
 
 		line.remove(QRegExp("[\\n\\r]"));	// remove any newline
 		if (simplifyWhitespacesEnabled)
 			line = line.simplified();
 
 		if (line.isEmpty() || line.startsWith(commentCharacter)) // skip empty or commented lines
 			continue;
 
 
 		QStringList lineStringList = line.split(m_separator, (QString::SplitBehavior)skipEmptyParts);
 		QDEBUG(" line = " << lineStringList);
 
 		QStringList lineString;
 		for (int n = 0; n < m_actualCols; ++n) {
 			// index column if required
 			if (n == 0 && createIndexEnabled) {
 				lineString += QString::number(i + 1);
 				continue;
 			}
 
 			if ((createIndexEnabled ? n - 1 : n) < lineStringList.size()) {
 				QString valueString = lineStringList.at(createIndexEnabled ? n - 1 : n);
 				//DEBUG(" valueString = " << valueString.toStdString());
 				if (skipEmptyParts && !QString::compare(valueString, " "))	// handle left white spaces
 					continue;
 
 				// set value depending on data type
 				switch (columnModes[n]) {
 				case AbstractColumn::Numeric: {
 					bool isNumber;
 					const double value = locale.toDouble(valueString, &isNumber);
 					lineString += QString::number(isNumber ? value : nanValue, 'g', 15);
 					break;
 				}
 				case AbstractColumn::Integer: {
 					bool isNumber;
 					const int value = locale.toInt(valueString, &isNumber);
 					lineString += QString::number(isNumber ? value : 0);
 					break;
 				}
 				case AbstractColumn::DateTime: {
 					const QDateTime valueDateTime = QDateTime::fromString(valueString, dateTimeFormat);
 					lineString += valueDateTime.isValid() ? valueDateTime.toString(dateTimeFormat) : QLatin1String(" ");
 					break;
 				}
 				case AbstractColumn::Text:
 					if (removeQuotesEnabled)
 						valueString.remove(QRegExp("[\"\']"));
 					lineString += valueString;
 					break;
 				case AbstractColumn::Month:	// never happens
 				case AbstractColumn::Day:
 					break;
 				}
 			} else 	// missing columns in this line
 				lineString += QLatin1String("");
 		}
 
 		dataStrings << lineString;
 	}
 
 	return dataStrings;
 }
 
 /*!
     writes the content of \c dataSource to the file \c fileName.
 */
 void AsciiFilterPrivate::write(const QString & fileName, AbstractDataSource* dataSource) {
 	Q_UNUSED(fileName);
 	Q_UNUSED(dataSource);
 
 	//TODO: save data to ascii file
 }
 
 //##############################################################################
 //##################  Serialization/Deserialization  ###########################
 //##############################################################################
 /*!
   Saves as XML.
  */
 void AsciiFilter::save(QXmlStreamWriter* writer) const {
 	writer->writeStartElement( "asciiFilter");
 	writer->writeAttribute( "commentCharacter", d->commentCharacter);
 	writer->writeAttribute( "separatingCharacter", d->separatingCharacter);
 	writer->writeAttribute( "autoMode", QString::number(d->autoModeEnabled));
 	writer->writeAttribute( "createIndex", QString::number(d->createIndexEnabled));
 	writer->writeAttribute( "header", QString::number(d->headerEnabled));
 	writer->writeAttribute( "vectorNames", d->vectorNames.join(' '));
 	writer->writeAttribute( "skipEmptyParts", QString::number(d->skipEmptyParts));
 	writer->writeAttribute( "simplifyWhitespaces", QString::number(d->simplifyWhitespacesEnabled));
 	writer->writeAttribute( "nanValue", QString::number(d->nanValue));
 	writer->writeAttribute( "removeQuotes", QString::number(d->removeQuotesEnabled));
 	writer->writeAttribute( "startRow", QString::number(d->startRow));
 	writer->writeAttribute( "endRow", QString::number(d->endRow));
 	writer->writeAttribute( "startColumn", QString::number(d->startColumn));
 	writer->writeAttribute( "endColumn", QString::number(d->endColumn));
 
 	writer->writeEndElement();
 }
 
 /*!
   Loads from XML.
 */
 bool AsciiFilter::load(XmlStreamReader* reader) {
 	KLocalizedString attributeWarning = ki18n("Attribute '%1' missing or empty, default value is used");
 	QXmlStreamAttributes attribs = reader->attributes();
 
 	QString str = attribs.value("commentCharacter").toString();
 	if (str.isEmpty())
 		reader->raiseWarning(attributeWarning.subs("commentCharacter").toString());
 	else
 		d->commentCharacter = str;
 
 	str = attribs.value("separatingCharacter").toString();
 	if (str.isEmpty())
 		reader->raiseWarning(attributeWarning.subs("separatingCharacter").toString());
 	else
 		d->separatingCharacter = str;
 
 	str = attribs.value("createIndex").toString();
 	if (str.isEmpty())
 		reader->raiseWarning(attributeWarning.subs("createIndex").toString());
 	else
 		d->createIndexEnabled = str.toInt();
 
 	str = attribs.value("autoMode").toString();
 	if (str.isEmpty())
 		reader->raiseWarning(attributeWarning.subs("autoMode").toString());
 	else
 		d->autoModeEnabled = str.toInt();
 
 	str = attribs.value("header").toString();
 	if (str.isEmpty())
 		reader->raiseWarning(attributeWarning.subs("header").toString());
 	else
 		d->headerEnabled = str.toInt();
 
 	str = attribs.value("vectorNames").toString();
 	d->vectorNames = str.split(' '); //may be empty
 
 	str = attribs.value("simplifyWhitespaces").toString();
 	if (str.isEmpty())
 		reader->raiseWarning(attributeWarning.subs("simplifyWhitespaces").toString());
 	else
 		d->simplifyWhitespacesEnabled = str.toInt();
 
 	str = attribs.value("nanValue").toString();
 	if (str.isEmpty())
 		reader->raiseWarning(attributeWarning.subs("nanValue").toString());
 	else
 		d->nanValue = str.toDouble();
 
 	str = attribs.value("removeQuotes").toString();
 	if (str.isEmpty())
 		reader->raiseWarning(attributeWarning.subs("removeQuotes").toString());
 	else
 		d->removeQuotesEnabled = str.toInt();
 
 	str = attribs.value("skipEmptyParts").toString();
 	if (str.isEmpty())
 		reader->raiseWarning(attributeWarning.subs("skipEmptyParts").toString());
 	else
 		d->skipEmptyParts = str.toInt();
 
 	str = attribs.value("startRow").toString();
 	if (str.isEmpty())
 		reader->raiseWarning(attributeWarning.subs("startRow").toString());
 	else
 		d->startRow = str.toInt();
 
 	str = attribs.value("endRow").toString();
 	if (str.isEmpty())
 		reader->raiseWarning(attributeWarning.subs("endRow").toString());
 	else
 		d->endRow = str.toInt();
 
 	str = attribs.value("startColumn").toString();
 	if (str.isEmpty())
 		reader->raiseWarning(attributeWarning.subs("startColumn").toString());
 	else
 		d->startColumn = str.toInt();
 
 	str = attribs.value("endColumn").toString();
 	if (str.isEmpty())
 		reader->raiseWarning(attributeWarning.subs("endColumn").toString());
 	else
 		d->endColumn = str.toInt();
 
 	return true;
 }
 
 int AsciiFilterPrivate::isPrepared() {
     return m_prepared;
 }
 
 #ifdef HAVE_MQTT
 
 /*!
  * \brief Offers a preview about the data received by the topic
  * \param list
  * \param message
  * \param topic
  */
 void AsciiFilterPrivate::MQTTPreview(QVector<QStringList>& list, const QString& message, const QString& topic) {
 	QVector<QStringList> dataStrings;
 
 	if (!message.isEmpty()) {
 		qDebug()<<"ascii mqtt preview for: " << topic;
 
 		//check how many lines can be read
 		int linesToRead = 0;
 		QVector<QString> newData;
 		QStringList newDataList = message.split(QRegExp("\n|\r\n|\r"), QString::SkipEmptyParts);
 		for (auto& valueString : newDataList) {
 			QStringList splitString = valueString.split(' ', QString::SkipEmptyParts);
 			for (const auto& valueString2 : splitString) {
 				if (!valueString2.isEmpty() && !valueString2.startsWith(commentCharacter) ) {
 					linesToRead++;
 					newData.push_back(valueString2);
 				}
 			}
 		}
 		qDebug() <<" data investigated, lines to read: "<<linesToRead;
 
 		//if no lines can be read, then we don't modify the list
 		if (linesToRead == 0) {
 			//list = dataStrings;
 			return;
 		}
 
 		if(!list.isEmpty()) {
 			//if lines to read is smaller then the size of the list, we shrink the list
 			if(linesToRead < list.size()) {
 				int oldSize = list.size();
 				for(int i = 0; i < oldSize - linesToRead; ++i)
 					list.removeLast();
 			}
 			//otherwise we will only read until the size of the list
 			else if (linesToRead > list.size()) {
 				linesToRead = list.size();
 			}
 		}
 
 		//Determine the number of columns
 		int colSize = 0;
 		if(list.isEmpty()) {
 			if (createIndexEnabled)
 				colSize = 2;
 			else colSize = 1;
 		}
 		else
 			colSize = columnModes.size() + 1;
 
 		columnModes.resize(colSize);
 
 		//if this is the first topic, we check if index has to be added
 		if(list.isEmpty())
 			if (createIndexEnabled) {
 				columnModes[0] = AbstractColumn::ColumnMode::Integer;
 				vectorNames.prepend("index");
 			}
 
 		vectorNames.append( topic);
 		//Set the column mode for the topic
 		columnModes[colSize - 1] = AbstractFileFilter::columnMode(newData[0], dateTimeFormat, numberFormat);
 
 		//improve the column mode, based on the rest of the data
 		for(int i = 0; i < linesToRead; i++) {
 			QString tempLine = newData[i];
 			if (simplifyWhitespacesEnabled)
 				tempLine = tempLine.simplified();
 			AbstractColumn::ColumnMode mode = AbstractFileFilter::columnMode(tempLine, dateTimeFormat, numberFormat);
 
 			// numeric: integer -> numeric
 			if (mode == AbstractColumn::Numeric && columnModes[colSize - 1] == AbstractColumn::Integer) {
 				columnModes[colSize - 1] = mode;
 			}
 			// text: non text -> text
 			if ( (mode == AbstractColumn::Text) && (columnModes[colSize - 1] != AbstractColumn::Text) ) {
 				columnModes[colSize - 1] = mode;
 			}
 		}
 		int forStart = 0;
 		int forEnd = 0;
 
 		if (list.isEmpty()) {
 			forStart = 0;
 			forEnd = linesToRead;
 		}
 		else {
 			if (mqttPreviewFirstEmptyColCount == 0) {
 				dataStrings = list;
 				forStart = 0;
 				forEnd = dataStrings.size();
 			}
 			else {
 				forStart = 1;
 				forEnd = linesToRead;
 				dataStrings = list;
 				QLocale locale(numberFormat);
 				//this is the first column having values, after at least 1 empty column
 				//until now only one row was filled with NaN values, so for starters we fill this row with the new value
 				switch (columnModes[colSize - 1]) {
 				case AbstractColumn::Numeric: {
 					bool isNumber;
 					const double value = locale.toDouble(newData[0], &isNumber);
 					dataStrings[0] += QString::number(isNumber ? value : nanValue, 'g', 16);
 					break;
 				}
 				case AbstractColumn::Integer: {
 					bool isNumber;
 					const int value = locale.toInt(newData[0], &isNumber);
 					dataStrings[0]  += QString::number(isNumber ? value : 0);
 					break;
 				}
 				case AbstractColumn::DateTime: {
 					const QDateTime valueDateTime = QDateTime::fromString(newData[0], dateTimeFormat);
 					dataStrings[0]  += valueDateTime.isValid() ? valueDateTime.toString(dateTimeFormat) : QLatin1String(" ");
 					break;
 				}
 				case AbstractColumn::Text:
 					if (removeQuotesEnabled)
 						newData[0].remove(QRegExp("[\"\']"));
 					dataStrings[0]  += newData[0];
 					break;
 				case AbstractColumn::Month:	// never happens
 				case AbstractColumn::Day:
 					break;
 				}
 			}
 		}
 		//We add every forEnd-forStart values to the list
 		for (int i = forStart; i < forEnd; ++i) {
 			QString line = newData[i];
 
 			if (simplifyWhitespacesEnabled)
 				line = line.simplified();
 
 			//skip empty or commented lines
 			if (line.isEmpty() || line.startsWith(commentCharacter))
 				continue;
 
 			QLocale locale(numberFormat);
 
 			QStringList lineString;
 			//We don't have to do any preparation if there were already data containing topics
 			if(!list.isEmpty() &&  mqttPreviewFirstEmptyColCount == 0)
 				lineString = dataStrings[i];
 
 			//Add index if it is the case
 			if(list.isEmpty() || (!list.isEmpty() && mqttPreviewFirstEmptyColCount > 0) )
 				if (createIndexEnabled)
 					lineString += QString::number(i);
 
 			//If this is the first not empty topic, add nan value to all the empty topics before this one
 			if(!list.isEmpty() && mqttPreviewFirstEmptyColCount > 0){
 				for(int j = 0; j < mqttPreviewFirstEmptyColCount; j++) {
 					lineString += QString::number(nanValue, 'g', 16);
 				}
 			}
 
 			//Add the actual value to the topic
 			switch (columnModes[colSize - 1]) {
 			case AbstractColumn::Numeric: {
 				bool isNumber;
 				const double value = locale.toDouble(line, &isNumber);
 				lineString += QString::number(isNumber ? value : nanValue, 'g', 16);
 				break;
 			}
 			case AbstractColumn::Integer: {
 				bool isNumber;
 				const int value = locale.toInt(line, &isNumber);
 				lineString += QString::number(isNumber ? value : 0);
 				break;
 			}
 			case AbstractColumn::DateTime: {
 				const QDateTime valueDateTime = QDateTime::fromString(line, dateTimeFormat);
 				lineString += valueDateTime.isValid() ? valueDateTime.toString(dateTimeFormat) : QLatin1String(" ");
 				break;
 			}
 			case AbstractColumn::Text:
 				if (removeQuotesEnabled)
 					line.remove(QRegExp("[\"\']"));
 				lineString += line;
 				break;
 			case AbstractColumn::Month:	// never happens
 			case AbstractColumn::Day:
 				break;
 			}
 			qDebug()<<"column updated with value";
 
 			// if the list was empty, or this is the first not empty topic, we append the new line
 			if(list.isEmpty() || (!list.isEmpty() && mqttPreviewFirstEmptyColCount > 0))
 				dataStrings << lineString;
 			//Otherwise we update the already existing line
 			if (!list.isEmpty() && mqttPreviewFirstEmptyColCount == 0)
 				dataStrings[i] = lineString;
 		}
 		//The first empty topics were taken care of
 		if(mqttPreviewFirstEmptyColCount > 0) {
 			mqttPreviewFirstEmptyColCount = 0;
 		}
 	}
 	//the message is empty and there were only empty messages before this
 	else if (list.isEmpty() || (!list.isEmpty() && mqttPreviewFirstEmptyColCount > 0) ) {
 		//increment the counter
 		mqttPreviewFirstEmptyColCount ++;
 
 		//determine number of columns
 		int colSize;
 		if (mqttPreviewFirstEmptyColCount == 1){
 			if (createIndexEnabled)
 				colSize = 2;
 			else colSize = 1;
 		}
 		else
 			colSize = columnModes.size() + 1;
 		columnModes.resize(colSize);
 
 		//add index if needed
 		if (mqttPreviewFirstEmptyColCount == 1)
 			if (createIndexEnabled) {
 				columnModes[0] = AbstractColumn::ColumnMode::Integer;
 				vectorNames.prepend("index");
 			}
 
 		//Add new column fot the mepty topic
 		vectorNames.append( topic);
 		columnModes[colSize-1] = AbstractColumn::ColumnMode::Numeric;
 
 		//Add a NaN value to the topic's column
 		QStringList lineString;
 		if (mqttPreviewFirstEmptyColCount == 1) {
 			//Add index if needed
 			if(createIndexEnabled)
 				lineString += QString::number(0);
 			lineString += QString::number(nanValue, 'g', 16);
 			//Append since this is the first empty column
 			dataStrings << lineString;
 		}
 		else {
 			//Update the already existing line
 			dataStrings = list;
 			dataStrings[0] += QString::number(nanValue, 'g', 16);
 		}
 	}
 	//The message is empty but there already was a non empty message
 	else if(!list.isEmpty()) {
 		//Append vector name
 		vectorNames.append( topic);
 
 		int colSize = columnModes.size() + 1;
 		columnModes.resize(colSize);
 		columnModes[colSize-1] = AbstractColumn::ColumnMode::Numeric;
 		dataStrings = list;
 		//Add as many NaN values as many lines the list already has
 		for (int i = 0; i < dataStrings.size(); ++i) {
 			dataStrings[i] += QString::number(nanValue, 'g', 16);
 		}
 	}
 	//update the list
 	list = dataStrings;
 }
 
 /*!
  * \brief Returns the statistical data that is needed by the topic for its MQTTClient's will message
  * \param topic
  */
 QString AsciiFilterPrivate::MQTTColumnStatistics(const MQTTTopic* topic) const{
 	Column* tempColumn = topic->child<Column>(m_actualCols - 1);
 	QString statistics;
 
 	QVector<bool> willStatistics = topic->mqttClient()->willStatistics();
 	//Add every statistical data to the string, the flag of which is set true
 	for(int i = 0; i <= willStatistics.size(); i++) {
 		if(willStatistics[i]) {
 			switch (static_cast<MQTTClient::WillStatistics>(i) ) {
 			case MQTTClient::WillStatistics::ArithmeticMean:
 				statistics += QLatin1String("Arithmetic mean: ") + QString::number(tempColumn->statistics().arithmeticMean) + "\n";
 				break;
 			case MQTTClient::WillStatistics::ContraharmonicMean:
 				statistics += QLatin1String("Contraharmonic mean: ") + QString::number(tempColumn->statistics().contraharmonicMean) + "\n";
 				break;
 			case MQTTClient::WillStatistics::Entropy:
 				statistics += QLatin1String("Entropy: ") + QString::number(tempColumn->statistics().entropy) + "\n";
 				break;
 			case MQTTClient::WillStatistics::GeometricMean:
 				statistics += QLatin1String("Geometric mean: ") + QString::number(tempColumn->statistics().geometricMean) + "\n";
 				break;
 			case MQTTClient::WillStatistics::HarmonicMean:
 				statistics += QLatin1String("Harmonic mean: ") + QString::number(tempColumn->statistics().harmonicMean) + "\n";
 				break;
 			case MQTTClient::WillStatistics::Kurtosis:
 				statistics += QLatin1String("Kurtosis: ") + QString::number(tempColumn->statistics().kurtosis) + "\n";
 				break;
 			case MQTTClient::WillStatistics::Maximum:
 				statistics += QLatin1String("Maximum: ") + QString::number(tempColumn->statistics().maximum) + "\n";
 				break;
 			case MQTTClient::WillStatistics::MeanDeviation:
 				statistics += QLatin1String("Mean deviation: ") + QString::number(tempColumn->statistics().meanDeviation) + "\n";
 				break;
 			case MQTTClient::WillStatistics::MeanDeviationAroundMedian:
 				statistics += QLatin1String("Mean deviation around median: ") + QString::number(tempColumn->statistics().meanDeviationAroundMedian) + "\n";
 				break;
 			case MQTTClient::WillStatistics::Median:
 				statistics += QLatin1String("Median: ") + QString::number(tempColumn->statistics().median) + "\n";
 				break;
 			case MQTTClient::WillStatistics::MedianDeviation:
 				statistics += QLatin1String("Median deviation: ") + QString::number(tempColumn->statistics().medianDeviation) + "\n";
 				break;
 			case MQTTClient::WillStatistics::Minimum:
 				statistics += QLatin1String("Minimum: ") + QString::number(tempColumn->statistics().minimum) + "\n";
 				break;
 			case MQTTClient::WillStatistics::Skewness:
 				statistics += QLatin1String("Skewness: ") + QString::number(tempColumn->statistics().skewness) + "\n";
 				break;
 			case MQTTClient::WillStatistics::StandardDeviation:
 				statistics += QLatin1String("Standard deviation: ") + QString::number(tempColumn->statistics().standardDeviation) + "\n";
 				break;
 			case MQTTClient::WillStatistics::Variance:
 				statistics += QLatin1String("Variance: ") + QString::number(tempColumn->statistics().variance) + "\n";
 				break;
 			default:
 				break;
 			}
 		}
 	}
 	return statistics;
 }
 
 AbstractColumn::ColumnMode AsciiFilterPrivate::MQTTColumnMode() const{
 	return columnModes[m_actualCols - 1];
 }
 
 /*!
  * \brief reads the content of a message received by the topic.
  * Uses the settings defined in the MQTTTopic's MQTTClient
  * \param message
  * \param topic
  * \param dataSource
  */
 void AsciiFilterPrivate::readMQTTTopic(const QString& message, const QString& topic, AbstractDataSource*dataSource) {
 	//If the message is empty, there is nothing to do
 	if (message.isEmpty()) {
 		DEBUG("No new data available");
 		return;
 	}
 
 	MQTTTopic* spreadsheet = dynamic_cast<MQTTTopic*>(dataSource);
 
 	int keepNValues = spreadsheet->keepNValues();
 
 	if (!m_prepared) {
 		qDebug()<<"Start preparing filter for: " << spreadsheet->topicName();
 
 		//Prepare the filter
 		const int mqttPrepareError = prepareMQTTTopicToRead(message, topic);
 		if (mqttPrepareError != 0) {
 			DEBUG("Mqtt Prepare Error = " << mqttPrepareError);
 			qDebug()<<mqttPrepareError<<"  itt van baj mqttPrepareError";
 			return;
 		}
 
 		// prepare import for spreadsheet
 		spreadsheet->setUndoAware(false);
 		spreadsheet->resize(AbstractFileFilter::Replace, vectorNames, m_actualCols);
 		qDebug() << "fds resized to col: " << m_actualCols;
 		qDebug() << "fds rowCount: " << spreadsheet->rowCount();
 
 		//columns in a MQTTTopic don't have any manual changes.
 		//make the available columns undo unaware and suppress the "data changed" signal.
 		//data changes will be propagated via an explicit Column::setChanged() call once new data was read.
 		for (int i = 0; i < spreadsheet->childCount<Column>(); i++) {
 			spreadsheet->child<Column>(i)->setUndoAware(false);
 			spreadsheet->child<Column>(i)->setSuppressDataChangedSignal(true);
 		}
 
 		if (keepNValues == 0)
 			spreadsheet->setRowCount(m_actualRows > 1 ? m_actualRows : 1);
 		else {
 			spreadsheet->setRowCount(spreadsheet->keepNValues());
 			m_actualRows = spreadsheet->keepNValues();
 		}
 
 		m_dataContainer.resize(m_actualCols);
 
 		for (int n = 0; n < m_actualCols; ++n) {
 			// data() returns a void* which is a pointer to any data type (see ColumnPrivate.cpp)
 			spreadsheet->child<Column>(n)->setColumnMode(columnModes[n]);
 			switch (columnModes[n]) {
 			case AbstractColumn::Numeric: {
 				QVector<double>* vector = static_cast<QVector<double>* >(spreadsheet->child<Column>(n)->data());
 				vector->reserve(m_actualRows);
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 			case AbstractColumn::Integer: {
 				QVector<int>* vector = static_cast<QVector<int>* >(spreadsheet->child<Column>(n)->data());
 				vector->reserve(m_actualRows);
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 			case AbstractColumn::Text: {
 				QVector<QString>* vector = static_cast<QVector<QString>*>(spreadsheet->child<Column>(n)->data());
 				vector->reserve(m_actualRows);
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 			case AbstractColumn::DateTime: {
 				QVector<QDateTime>* vector = static_cast<QVector<QDateTime>* >(spreadsheet->child<Column>(n)->data());
 				vector->reserve(m_actualRows);
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 				//TODO
 			case AbstractColumn::Month:
 			case AbstractColumn::Day:
 				break;
 			}
 		}
 	}
 
 #ifdef PERFTRACE_LIVE_IMPORT
 	PERFTRACE("AsciiLiveDataImportTotal: ");
 #endif
 
 	MQTTClient::ReadingType readingType;
 	if (!m_prepared) {
 		//if filter is not prepared we read till the end
 		readingType = MQTTClient::ReadingType::TillEnd;
 	} else {
 		//we have to read all the data when reading from end
 		//so we set readingType to TillEnd
 		if (spreadsheet->readingType() == MQTTClient::ReadingType::FromEnd) {
 			readingType = MQTTClient::ReadingType::TillEnd;
 		} else {
 			readingType = static_cast<MQTTClient::ReadingType>(spreadsheet->readingType());
 		}
 	}
 
 	//count the new lines, increase actualrows on each
 	//now we read all the new lines, if we want to use sample rate
 	//then here we can do it, if we have actually sample rate number of lines :-?
 	int newLinesForSampleSizeNotTillEnd = 0;
 	int newLinesTillEnd = 0;
 	QVector<QString> newData;
 	if (readingType != MQTTClient::ReadingType::TillEnd) {
 		newData.reserve(spreadsheet->sampleSize());
 		newData.resize(spreadsheet->sampleSize());
 	}
 
 	int newDataIdx = 0;
 	bool sampleSizeReached = false;
 	{
 #ifdef PERFTRACE_LIVE_IMPORT
 		PERFTRACE("AsciiLiveDataImportReadingFromFile: ");
 #endif
 		QStringList newDataList = message.split(QRegExp("\n|\r\n|\r"), QString::SkipEmptyParts);
 		for (auto& valueString : newDataList) {			
 			if(!valueString.startsWith(commentCharacter)) {
 
 				QStringList splitString = valueString.split(m_separator, static_cast<QString::SplitBehavior>(skipEmptyParts));
 
 				for (const auto& valueString2 : splitString) {
 					if (!valueString2.isEmpty() && !valueString2.startsWith(commentCharacter)) {
 
 						if (readingType != MQTTClient::ReadingType::TillEnd)
 							newData[newDataIdx++] = valueString2;
 						else
 							newData.push_back(valueString2);
 						newLinesTillEnd++;
 
 						if (readingType != MQTTClient::ReadingType::TillEnd) {
 							newLinesForSampleSizeNotTillEnd++;
 							//for Continuous reading and FromEnd we read sample rate number of lines if possible
 							if (newLinesForSampleSizeNotTillEnd == spreadsheet->sampleSize()) {
 								sampleSizeReached = true;
 								break;
 							}
 						}
 					}
 				}
 				//if the sample size limit is reached we brake from the outer loop as well
 				if(sampleSizeReached)
 					break;
 			}
 		}
 	}
 
 	qDebug()<<"Processing message done";
 	//now we reset the readingType
 	if (static_cast<MQTTClient::ReadingType>(spreadsheet->readingType()) == MQTTClient::ReadingType::FromEnd)
 		readingType = static_cast<MQTTClient::ReadingType>(spreadsheet->readingType());
 
 	//we had less new lines than the sample rate specified
 	if (readingType != MQTTClient::ReadingType::TillEnd)
 		qDebug() << "Removed empty lines: " << newData.removeAll("");
 
 	qDebug()<<"Create index enabled:  "<<createIndexEnabled;
 
 	const int spreadsheetRowCountBeforeResize = spreadsheet->rowCount();;
 
 	if(m_prepared ) {
 		if (keepNValues == 0)
 			m_actualRows = spreadsheetRowCountBeforeResize;
 		else {
 			//if the keepNValues changed since the last read we have to manage the columns accordingly
 			if(m_actualRows != spreadsheet->keepNValues()) {
 				if(m_actualRows < spreadsheet->keepNValues()) {
 					spreadsheet->setRowCount(spreadsheet->keepNValues());
 					qDebug()<<"rowcount set to: " << spreadsheet->keepNValues();
 				}
 
 				//Calculate the difference between the old and new keepNValues
 				int rowDiff = 0;
 				if(m_actualRows > spreadsheet->keepNValues()) {
 					rowDiff = m_actualRows -  spreadsheet->keepNValues();
 				}
 				if(m_actualRows < spreadsheet->keepNValues()) {
 					rowDiff =spreadsheet->keepNValues() - m_actualRows;
 				}
 
 				for (int n = 0; n < columnModes.size(); ++n) {
 					// data() returns a void* which is a pointer to any data type (see ColumnPrivate.cpp)
 					switch (columnModes[n]) {
 					case AbstractColumn::Numeric: {
 						QVector<double>*  vector = static_cast<QVector<double>* >(spreadsheet->child<Column>(n)->data());
 						m_dataContainer[n] = static_cast<void *>(vector);
 
 						//if the keepNValues got smaller then we move the last keepNValues count of data
 						//in the first keepNValues places
 						if(m_actualRows > spreadsheet->keepNValues()) {
 							for(int i = 0; i < spreadsheet->keepNValues(); i++) {
 								static_cast<QVector<double>*>(m_dataContainer[n])->operator[] (i) =
 										static_cast<QVector<double>*>(m_dataContainer[n])->operator[](m_actualRows - spreadsheet->keepNValues() + i);
 							}
 						}
 
 						//if the keepNValues got bigger we move the existing values to the last m_actualRows positions
 						//then fill the remaining lines with NaN
 						if(m_actualRows < spreadsheet->keepNValues()) {
 							vector->reserve( spreadsheet->keepNValues());
 							vector->resize( spreadsheet->keepNValues());
 
 							for(int i = 1; i <= m_actualRows; i++) {
 								static_cast<QVector<double>*>(m_dataContainer[n])->operator[] (spreadsheet->keepNValues() - i) =
 										static_cast<QVector<double>*>(m_dataContainer[n])->operator[](spreadsheet->keepNValues() - i - rowDiff);
 							}
 							for(int i = 0; i < rowDiff; i++) {
 								static_cast<QVector<double>*>(m_dataContainer[n])->operator[](i) = nanValue;
 							}
 						}
 						break;
 					}
 					case AbstractColumn::Integer: {
 						QVector<int>* vector = static_cast<QVector<int>* >(spreadsheet->child<Column>(n)->data());
 						m_dataContainer[n] = static_cast<void *>(vector);
 
 						//if the keepNValues got smaller then we move the last keepNValues count of data
 						//in the first keepNValues places
 						if(m_actualRows > spreadsheet->keepNValues()) {
 							for(int i = 0; i < spreadsheet->keepNValues(); i++) {
 								static_cast<QVector<int>*>(m_dataContainer[n])->operator[] (i) =
 										static_cast<QVector<int>*>(m_dataContainer[n])->operator[](m_actualRows - spreadsheet->keepNValues() + i);
 							}
 						}
 
 						//if the keepNValues got bigger we move the existing values to the last m_actualRows positions
 						//then fill the remaining lines with 0
 						if(m_actualRows < spreadsheet->keepNValues()) {
 							vector->reserve( spreadsheet->keepNValues());
 							vector->resize( spreadsheet->keepNValues());
 							for(int i = 1; i <= m_actualRows; i++) {
 								static_cast<QVector<int>*>(m_dataContainer[n])->operator[] (spreadsheet->keepNValues() - i) =
 										static_cast<QVector<int>*>(m_dataContainer[n])->operator[](spreadsheet->keepNValues() - i - rowDiff);
 							}
 							for(int i = 0; i < rowDiff; i++){
 								static_cast<QVector<int>*>(m_dataContainer[n])->operator[](i) = 0;
 							}
 						}
 						break;
 					}
 					case AbstractColumn::Text: {
 						QVector<QString>* vector = static_cast<QVector<QString>*>(spreadsheet->child<Column>(n)->data());
 						m_dataContainer[n] = static_cast<void *>(vector);
 
 						//if the keepNValues got smaller then we move the last keepNValues count of data
 						//in the first keepNValues places
 						if(m_actualRows > spreadsheet->keepNValues()) {
 							for(int i = 0; i < spreadsheet->keepNValues(); i++) {
 								static_cast<QVector<QString>*>(m_dataContainer[n])->operator[] (i) =
 										static_cast<QVector<QString>*>(m_dataContainer[n])->operator[](m_actualRows - spreadsheet->keepNValues() + i);
 							}
 						}
 
 						//if the keepNValues got bigger we move the existing values to the last m_actualRows positions
 						//then fill the remaining lines with ""
 						if(m_actualRows < spreadsheet->keepNValues()) {
 							vector->reserve( spreadsheet->keepNValues());
 							vector->resize( spreadsheet->keepNValues());
 							for(int i = 1; i <= m_actualRows; i++) {
 								static_cast<QVector<QString>*>(m_dataContainer[n])->operator[] (spreadsheet->keepNValues() - i) =
 										static_cast<QVector<QString>*>(m_dataContainer[n])->operator[](spreadsheet->keepNValues() - i - rowDiff);
 							}
 							for(int i = 0; i < rowDiff; i++)
 								static_cast<QVector<QString>*>(m_dataContainer[n])->operator[](i) = "";
 						}
 						break;
 					}
 					case AbstractColumn::DateTime: {
 						QVector<QDateTime>* vector = static_cast<QVector<QDateTime>* >(spreadsheet->child<Column>(n)->data());
 						m_dataContainer[n] = static_cast<void *>(vector);
 
 						//if the keepNValues got smaller then we move the last keepNValues count of data
 						//in the first keepNValues places
 						if(m_actualRows > spreadsheet->keepNValues()) {
 							for(int i = 0; i < spreadsheet->keepNValues(); i++) {
 								static_cast<QVector<QDateTime>*>(m_dataContainer[n])->operator[] (i) =
 										static_cast<QVector<QDateTime>*>(m_dataContainer[n])->operator[](m_actualRows - spreadsheet->keepNValues() + i);
 							}
 						}
 
 						//if the keepNValues got bigger we move the existing values to the last m_actualRows positions
 						//then fill the remaining lines with null datetime
 						if(m_actualRows < spreadsheet->keepNValues()) {
 							vector->reserve( spreadsheet->keepNValues());
 							vector->resize( spreadsheet->keepNValues());
 							for(int i = 1; i <= m_actualRows; i++) {
 								static_cast<QVector<QDateTime>*>(m_dataContainer[n])->operator[] (spreadsheet->keepNValues() - i) =
 										static_cast<QVector<QDateTime>*>(m_dataContainer[n])->operator[](spreadsheet->keepNValues() - i - rowDiff);
 							}
 							for(int i = 0; i < rowDiff; i++)
 								static_cast<QVector<QDateTime>*>(m_dataContainer[n])->operator[](i) = QDateTime();
 						}
 						break;
 					}
 						//TODO
 					case AbstractColumn::Month:
 					case AbstractColumn::Day:
 						break;
 					}
 				}
 				//if the keepNValues got smaller resize the spreadsheet
 				if(m_actualRows > spreadsheet->keepNValues())
 					spreadsheet->setRowCount(spreadsheet->keepNValues());
 
 				//set the new row count
 				m_actualRows = spreadsheet->keepNValues();
 				qDebug()<<"actual rows: "<<m_actualRows;
 			}
 		}
 	}
 
 	qDebug()<<"starting m_actual rows calculated: " << m_actualRows <<", new data size: "<<newData.size();
 
 	int currentRow = 0; // indexes the position in the vector(column)
 	int linesToRead = 0;
 
 	if (m_prepared) {
 		//increase row count if we don't have a fixed size
 		//but only after the preparation step
 		if (keepNValues == 0) {
 			if (readingType != MQTTClient::ReadingType::TillEnd)
 				m_actualRows += qMin(newData.size(), spreadsheet->sampleSize());
 			else {
 				m_actualRows += newData.size();
 			}
 		}
 
 		//fixed size
 		if (keepNValues != 0) {
 			if (readingType == MQTTClient::ReadingType::TillEnd) {
 				//we had more lines than the fixed size, so we read m_actualRows number of lines
 				if (newLinesTillEnd > m_actualRows) {
 					linesToRead = m_actualRows;
 				} else
 					linesToRead = newLinesTillEnd;
 			} else {
 				//we read max sample size number of lines when the reading mode
 				//is ContinuouslyFixed or FromEnd
 				if(spreadsheet->sampleSize() <= spreadsheet->keepNValues())
 					linesToRead = qMin(spreadsheet->sampleSize(), newLinesTillEnd);
 				else
 					linesToRead = qMin(spreadsheet->keepNValues(), newLinesTillEnd);
 			}
 		} else {
 			linesToRead = m_actualRows - spreadsheetRowCountBeforeResize;
 		}
 
 		if (linesToRead == 0)
 			return;
 
 	} else {
 		if(keepNValues != 0) {
 			linesToRead = newLinesTillEnd > m_actualRows ? m_actualRows : newLinesTillEnd;
 		}
 		else {
 			linesToRead = newLinesTillEnd;
 		}
 	}
 	qDebug()<<"linestoread = " << linesToRead;
 
 	//new rows/resize columns if we don't have a fixed size
 	if (keepNValues == 0) {
 
 #ifdef PERFTRACE_LIVE_IMPORT
 		PERFTRACE("AsciiLiveDataImportResizing: ");
 #endif
 		if (spreadsheet->rowCount() < m_actualRows)
 			spreadsheet->setRowCount(m_actualRows);
 
 		if (!m_prepared)
 			currentRow = 0;
 		else {
 			// indexes the position in the vector(column)
 			currentRow = spreadsheetRowCountBeforeResize;
 		}
 
 		// if we have fixed size, we do this only once in preparation, here we can use
 		// m_prepared and we need something to decide whether it has a fixed size or increasing
 
 		for (int n = 0; n < m_actualCols; ++n) {
 			// data() returns a void* which is a pointer to any data type (see ColumnPrivate.cpp)
 			switch (columnModes[n]) {
 			case AbstractColumn::Numeric: {
 				QVector<double>* vector = static_cast<QVector<double>* >(spreadsheet->child<Column>(n)->data());
 				vector->reserve(m_actualRows);
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 			case AbstractColumn::Integer: {
 				QVector<int>* vector = static_cast<QVector<int>* >(spreadsheet->child<Column>(n)->data());
 				vector->reserve(m_actualRows);
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 			case AbstractColumn::Text: {
 				QVector<QString>* vector = static_cast<QVector<QString>*>(spreadsheet->child<Column>(n)->data());
 				vector->reserve(m_actualRows);
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 			case AbstractColumn::DateTime: {
 				QVector<QDateTime>* vector = static_cast<QVector<QDateTime>* >(spreadsheet->child<Column>(n)->data());
 				vector->reserve(m_actualRows);
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 				//TODO
 			case AbstractColumn::Month:
 			case AbstractColumn::Day:
 				break;
 			}
 		}
 	} else {
 		//when we have a fixed size we have to pop sampleSize number of lines if specified
 		//here popping, setting currentRow
 		if (!m_prepared)
 			currentRow = m_actualRows - qMin(newLinesTillEnd, m_actualRows);
 		else {
 			if (readingType == MQTTClient::ReadingType::TillEnd) {
 				if (newLinesTillEnd > m_actualRows)
 					currentRow = 0;
 				else {
 					currentRow = m_actualRows - newLinesTillEnd;
 				}
 			} else {
 				//we read max sample rate number of lines when the reading mode
 				//is ContinuouslyFixed or FromEnd
 				currentRow = m_actualRows - linesToRead;
 			}
 		}
 
 		if (m_prepared) {
 #ifdef PERFTRACE_LIVE_IMPORT
 			PERFTRACE("AsciiLiveDataImportPopping: ");
 #endif
 			for (int row = 0; row < linesToRead; ++row) {
 				for (int col = 0;  col < m_actualCols; ++col) {
 					switch (columnModes[col]) {
 					case AbstractColumn::Numeric: {
 						QVector<double>* vector = static_cast<QVector<double>* >(spreadsheet->child<Column>(col)->data());
 						vector->pop_front();
 						vector->reserve(m_actualRows);
 						vector->resize(m_actualRows);
 						m_dataContainer[col] = static_cast<void *>(vector);
 						break;
 					}
 					case AbstractColumn::Integer: {
 						QVector<int>* vector = static_cast<QVector<int>* >(spreadsheet->child<Column>(col)->data());
 						vector->pop_front();
 						vector->reserve(m_actualRows);
 						vector->resize(m_actualRows);
 						m_dataContainer[col] = static_cast<void *>(vector);
 						break;
 					}
 					case AbstractColumn::Text: {
 						QVector<QString>* vector = static_cast<QVector<QString>*>(spreadsheet->child<Column>(col)->data());
 						vector->pop_front();
 						vector->reserve(m_actualRows);
 						vector->resize(m_actualRows);
 						m_dataContainer[col] = static_cast<void *>(vector);
 						break;
 					}
 					case AbstractColumn::DateTime: {
 						QVector<QDateTime>* vector = static_cast<QVector<QDateTime>* >(spreadsheet->child<Column>(col)->data());
 						vector->pop_front();
 						vector->reserve(m_actualRows);
 						vector->resize(m_actualRows);
 						m_dataContainer[col] = static_cast<void *>(vector);
 						break;
 					}
 						//TODO
 					case AbstractColumn::Month:
 					case AbstractColumn::Day:
 						break;
 					}
 				}
 			}
 		}
 	}
 
 	// from the last row we read the new data in the spreadsheet
 	qDebug() << "reading from line: "  << currentRow << " lines till end: " << newLinesTillEnd;
 	qDebug() << "Lines to read: " << linesToRead <<" actual rows: " << m_actualRows;
 	newDataIdx = 0;
 	//From end means that we read the last sample size amount of data
 	if (readingType == MQTTClient::ReadingType::FromEnd) {
 		if (m_prepared) {
 			if (newData.size() > spreadsheet->sampleSize())
 				newDataIdx = newData.size() - spreadsheet->sampleSize();
 		}
 	}
 
 	qDebug() << "newDataIdx: " << newDataIdx;
 	static int indexColumnIdx = 0;
 	{
 #ifdef PERFTRACE_LIVE_IMPORT
 		PERFTRACE("AsciiLiveDataImportFillingContainers: ");
 #endif
 		int row = 0;
 		for (; row < linesToRead; ++row) {
 			QString line;
 			if (readingType == MQTTClient::ReadingType::FromEnd)
 				line = newData.at(newDataIdx++);
 			else
 				line = newData.at(row);
 
 			if (simplifyWhitespacesEnabled)
 				line = line.simplified();
 
 			if (line.isEmpty() || line.startsWith(commentCharacter))
 			{
 				qDebug()<<"found empty line     "<<currentRow;
 				continue;
 			}
 
 			QLocale locale(numberFormat);
 
 			int col = 0;
 			//Add index if needed
 			if (createIndexEnabled) {
 				col = 1;
 				QString tempIndex;
 				if (keepNValues != 0)
 					tempIndex = QString::number(indexColumnIdx++);
 				else
 					tempIndex = QString::number(currentRow);
 				switch (columnModes[0]) {
 				case AbstractColumn::Numeric: {
 					bool isNumber;
 					const double value = locale.toDouble(tempIndex, &isNumber);
 					static_cast<QVector<double>*>(m_dataContainer[0])->operator[](currentRow) = (isNumber ? value : nanValue);
 					break;
 				}
 				case AbstractColumn::Integer: {
 					bool isNumber;
 					const int value = locale.toInt(tempIndex, &isNumber);
 					static_cast<QVector<int>*>(m_dataContainer[0])->operator[](currentRow) = (isNumber ? value : 0);
 					break;
 				}
 				case AbstractColumn::DateTime: {
 					const QDateTime valueDateTime = QDateTime::fromString(tempIndex, dateTimeFormat);
 					static_cast<QVector<QDateTime>*>(m_dataContainer[0])->operator[](currentRow) = valueDateTime.isValid() ? valueDateTime : QDateTime();
 					break;
 				}
 				case AbstractColumn::Text:
 					if (removeQuotesEnabled)
 						tempIndex.remove(QRegExp("[\"\']"));
 					static_cast<QVector<QString>*>(m_dataContainer[0])->operator[](currentRow) = tempIndex;
 					break;
 				case AbstractColumn::Month:
 					//TODO
 					break;
 				case AbstractColumn::Day:
 					//TODO
 					break;
 				}
 			}
 
 			//setting timestamp on current time
 			static_cast<QVector<QDateTime>*>(m_dataContainer[col])->operator[](currentRow) =  QDateTime::currentDateTime();
 
 			QString valueString = line;
 			qDebug() << "putting in " << valueString << " in line: " << currentRow;
 
 			// set value depending on data type
 			switch (columnModes[m_actualCols - 1]) {
 			case AbstractColumn::Numeric: {
 				bool isNumber;
 				const double value = locale.toDouble(valueString, &isNumber);
 				static_cast<QVector<double>*>(m_dataContainer[m_actualCols - 1])->operator[](currentRow) = (isNumber ? value : nanValue);
 				break;
 			}
 			case AbstractColumn::Integer: {
 				bool isNumber;
 				const int value = locale.toInt(valueString, &isNumber);
 				static_cast<QVector<int>*>(m_dataContainer[m_actualCols - 1])->operator[](currentRow) = (isNumber ? value : 0);
 				break;
 			}
 			case AbstractColumn::DateTime: {
 				const QDateTime valueDateTime = QDateTime::fromString(valueString, dateTimeFormat);
 				static_cast<QVector<QDateTime>*>(m_dataContainer[m_actualCols - 1])->operator[](currentRow) = valueDateTime.isValid() ? valueDateTime : QDateTime();
 				break;
 			}
 			case AbstractColumn::Text:
 				if (removeQuotesEnabled)
 					valueString.remove(QRegExp("[\"\']"));
 				static_cast<QVector<QString>*>(m_dataContainer[m_actualCols - 1])->operator[](currentRow) = valueString;
 				break;
 			case AbstractColumn::Month:
 				//TODO
 				break;
 			case AbstractColumn::Day:
 				//TODO
 				break;
 			}
 
 			currentRow++;
 		}
 	}
 
 	if (m_prepared) {
 		qDebug()<<"notifying plots";
 		//notify all affected columns and plots about the changes
 		PERFTRACE("AsciiLiveDataImport, notify affected columns and plots");
 
 		const Project* project = spreadsheet->project();
 		QVector<const XYCurve*> curves = project->children<const XYCurve>(AbstractAspect::Recursive);
 		QVector<CartesianPlot*> plots;
 
 		qDebug()<<"Uploading plots";
 		for (int n = 0; n < m_actualCols; ++n) {
 			Column* column = spreadsheet->column(n);
 
 			//determine the plots where the column is consumed
 			for (const auto* curve : curves) {
 				if (curve->xColumn() == column || curve->yColumn() == column) {
 					CartesianPlot* plot = dynamic_cast<CartesianPlot*>(curve->parentAspect());
 					if (plots.indexOf(plot) == -1) {
 						plots << plot;
 						plot->setSuppressDataChangedSignal(true);
 					}
 				}
 			}
 
 			column->setChanged();
 		}
 
 		//loop over all affected plots and retransform them
 		for (auto* const plot : plots) {
 			//TODO setting this back to true triggers again a lot of retransforms in the plot (one for each curve).
 			// 				plot->setSuppressDataChangedSignal(false);
 			plot->dataChanged();
 		}
 	}
 
 	//Set prepared true if needed
 	if(!m_prepared)
 		m_prepared = true;
 }
 
 /*!
  * \brief Prepares the filter to read from messages received by the MQTTTopic.
  * Returns whether the preparation was successful or not
  * \param message
  * \param topic
  */
 int AsciiFilterPrivate::prepareMQTTTopicToRead(const QString& message,  const QString& topic) {
 	Q_UNUSED(topic)
 	vectorNames.append("value");
 	if (endColumn == -1)
 		endColumn = 1;
 	else endColumn++;
 
 	vectorNames.prepend("timestamp");
 	endColumn++;
 
 	if (createIndexEnabled) {
 		vectorNames.prepend("index");
 		endColumn++;
 	}
 
 	m_actualCols = endColumn - startColumn + 1;
 	qDebug()<<"actual cols: "<<m_actualCols;
 
 	QStringList lineList = message.split(QRegExp("\n|\r\n|\r"), QString::SkipEmptyParts);
 	QString firstLine = lineList.takeFirst();
 	firstLine.remove(QRegExp("[\\n\\r]"));	// remove any newline
 	if (simplifyWhitespacesEnabled)
 		firstLine = firstLine.simplified();
 	DEBUG("First line: \'" << firstLine.toStdString() << '\'');
 
 	// determine separator and split first line
 	QStringList firstLineStringList;
 	if (separatingCharacter == "auto") {
 		DEBUG("automatic separator");
 		QRegExp regExp("(\\s+)|(,\\s+)|(;\\s+)|(:\\s+)");
 		firstLineStringList = firstLine.split(regExp, (QString::SplitBehavior)skipEmptyParts);
 
 		if (!firstLineStringList.isEmpty()) {
 			int length1 = firstLineStringList.at(0).length();
 			if (firstLineStringList.size() > 1) {
 				int pos2 = firstLine.indexOf(firstLineStringList.at(1), length1);
 				m_separator = firstLine.mid(length1, pos2 - length1);
 			} else {
 				//old: separator = line.right(line.length() - length1);
 				m_separator = ' ';
 			}
 		}
 	} else {	// use given separator
 		// replace symbolic "TAB" with '\t'
 		m_separator = separatingCharacter.replace(QLatin1String("2xTAB"), "\t\t", Qt::CaseInsensitive);
 		m_separator = separatingCharacter.replace(QLatin1String("TAB"), "\t", Qt::CaseInsensitive);
 		// replace symbolic "SPACE" with ' '
 		m_separator = m_separator.replace(QLatin1String("2xSPACE"), QLatin1String("  "), Qt::CaseInsensitive);
 		m_separator = m_separator.replace(QLatin1String("3xSPACE"), QLatin1String("   "), Qt::CaseInsensitive);
 		m_separator = m_separator.replace(QLatin1String("4xSPACE"), QLatin1String("    "), Qt::CaseInsensitive);
 		m_separator = m_separator.replace(QLatin1String("SPACE"), QLatin1String(" "), Qt::CaseInsensitive);
 		firstLineStringList = firstLine.split(m_separator, (QString::SplitBehavior)skipEmptyParts);
 	}
 	DEBUG("separator: \'" << m_separator.toStdString() << '\'');
 	DEBUG("number of columns: " << firstLineStringList.size());
 	QDEBUG("first line: " << firstLineStringList);
 	DEBUG("headerEnabled = " << headerEnabled);
 	// parse first data line to determine data type for each column
 	columnModes.resize(m_actualCols);
 	int col = 0;
 	if (createIndexEnabled) {
 		columnModes[0] = AbstractColumn::Integer;
 		col = 1;
 	}
 
 	//set column mode for timestamp
 	columnModes[col] = AbstractColumn::DateTime;
 	col++;
 
 	auto firstValue = firstLineStringList.takeFirst();//use first value to identify column mode	
 	while(firstValue.isEmpty() || firstValue.startsWith(commentCharacter) )//get the first usable value
 		firstValue = firstLineStringList.takeFirst();
 
 	if (simplifyWhitespacesEnabled)
 		firstValue = firstValue.simplified();
 
 	columnModes[m_actualCols-1] = AbstractFileFilter::columnMode(firstValue, dateTimeFormat, numberFormat);
 
 	//Improve the column mode based on the other values from the first line
 	for (auto& valueString : firstLineStringList) {
 		if(!valueString.isEmpty() && !valueString.startsWith(commentCharacter) ){
 			if (createIndexEnabled)
 				col = 1;
 			else
 				col = 0;
 
 			if (simplifyWhitespacesEnabled)
 				valueString = valueString.simplified();
 			AbstractColumn::ColumnMode mode = AbstractFileFilter::columnMode(valueString, dateTimeFormat, numberFormat);
 
 			// numeric: integer -> numeric
 			if (mode == AbstractColumn::Numeric && columnModes[m_actualCols-1] == AbstractColumn::Integer) {
 				columnModes[m_actualCols-1] = mode;
 			}
 			// text: non text -> text
 			if (mode == AbstractColumn::Text && columnModes[m_actualCols-1] != AbstractColumn::Text) {
 				columnModes[m_actualCols-1] = mode;
 			}
 		}
 	}
 	//Improve the column mode based on the remaining values
 	for (auto& valueString : lineList) {
 		QStringList splitString = valueString.split(m_separator, (QString::SplitBehavior)skipEmptyParts);
 		for (auto& valueString2 : splitString) {
 			if (!valueString2.isEmpty() && !valueString2.startsWith(commentCharacter)) {
 
 				if (simplifyWhitespacesEnabled)
 					valueString2 = valueString2.simplified();
 				AbstractColumn::ColumnMode mode = AbstractFileFilter::columnMode(valueString2, dateTimeFormat, numberFormat);
 
 				// numeric: integer -> numeric
 				if (mode == AbstractColumn::Numeric && columnModes[m_actualCols-1] == AbstractColumn::Integer) {
 					columnModes[m_actualCols-1] = mode;
 				}
 				// text: non text -> text
 				if (mode == AbstractColumn::Text && columnModes[m_actualCols-1] != AbstractColumn::Text) {
 					columnModes[m_actualCols-1] = mode;
 				}
 			}
 		}
 	}
 
 	//determine rowcount
 	int tempRowCount = 0;
 	QStringList newDataList = message.split(QRegExp("\n|\r\n|\r"), QString::SkipEmptyParts);
 	for (auto& valueString : newDataList) {
 		if(!valueString.startsWith(commentCharacter)) {
 			QStringList splitString = valueString.split(m_separator, (QString::SplitBehavior)skipEmptyParts);
 			for (auto& valueString2 : splitString) {
 				if (!valueString2.isEmpty() && !valueString2.startsWith(commentCharacter)) {
 					tempRowCount ++;
 				}
 			}
 		}
 	}
 
 	QDEBUG("column modes = " << columnModes);
 	m_actualRows = tempRowCount;
 
 	/////////////////////////////////////////////////////////////////
 
 	int actualEndRow = endRow;
 	DEBUG("endRow = " << endRow);
 	if (endRow == -1 || endRow > m_actualRows)
 		actualEndRow = m_actualRows;
 
 	if (m_actualRows > actualEndRow)
 		m_actualRows = actualEndRow;
 
 
 	DEBUG("start/end column: " << startColumn << ' ' << endColumn);
 	DEBUG("start/end row: " << m_actualStartRow << ' ' << actualEndRow);
 	DEBUG("actual cols/rows (w/o header incl. start rows): " << m_actualCols << ' ' << m_actualRows);
 
 	return 0;
 }
 
 /*!
  * \brief After the MQTTTopic was loaded, the filter is prepared for reading
  * \param prepared
  * \param topic
  * \param separator
  */
 void AsciiFilterPrivate::setPreparedForMQTT(bool prepared, MQTTTopic *topic, const QString& separator) {
 	m_prepared = prepared;
 	//If originally it was prepared we have to restore the settings
 	if(prepared == true) {
 		m_separator = separator;
 		m_actualCols = endColumn - startColumn + 1;
 		m_actualRows = topic->rowCount();
 		//set the column modes
 		columnModes.resize(topic->columnCount());
 		for(int i = 0; i < topic->columnCount(); ++i) {
 			columnModes[i] = topic->column(i)->columnMode();
 		}
 		//set the data containers
 		m_dataContainer.resize(m_actualCols);
 		for (int n = 0; n < m_actualCols; ++n) {
 			// data() returns a void* which is a pointer to any data type (see ColumnPrivate.cpp)
 			topic->child<Column>(n)->setColumnMode(columnModes[n]);
 			switch (columnModes[n]) {
 			case AbstractColumn::Numeric: {
 				QVector<double>* vector = static_cast<QVector<double>* >(topic->child<Column>(n)->data());
 				vector->reserve(m_actualRows);
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 			case AbstractColumn::Integer: {
 				QVector<int>* vector = static_cast<QVector<int>* >(topic->child<Column>(n)->data());
 				vector->reserve(m_actualRows);
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 			case AbstractColumn::Text: {
 				QVector<QString>* vector = static_cast<QVector<QString>*>(topic->child<Column>(n)->data());
 				vector->reserve(m_actualRows);
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 			case AbstractColumn::DateTime: {
 				QVector<QDateTime>* vector = static_cast<QVector<QDateTime>* >(topic->child<Column>(n)->data());
 				vector->reserve(m_actualRows);
 				vector->resize(m_actualRows);
 				m_dataContainer[n] = static_cast<void *>(vector);
 				break;
 			}
 				//TODO
 			case AbstractColumn::Month:
 			case AbstractColumn::Day:
 				break;
 			}
 		}
 	}
 }
 #endif
 
 /*!
  * \brief Returns the separator used by the filter
  * \return
  */
 QString AsciiFilterPrivate::separator() const {
 	return m_separator;
 }
diff --git a/src/backend/matrix/Matrix.cpp b/src/backend/matrix/Matrix.cpp
index a46239ff7..3676644f0 100644
--- a/src/backend/matrix/Matrix.cpp
+++ b/src/backend/matrix/Matrix.cpp
@@ -1,1297 +1,1293 @@
 
 /***************************************************************************
     File                 : Matrix.cpp
     Project              : Matrix
     Description          : Spreadsheet with a MxN matrix data model
     --------------------------------------------------------------------
     Copyright            : (C) 2008-2009 Tilman Benkert (thzs@gmx.net)
     Copyright            : (C) 2015-2017 Alexander Semke (alexander.semke@web.de)
     Copyright            : (C) 2017-2018 Stefan Gerlach (stefan.gerlach@uni.kn)
 
  ***************************************************************************/
 
 /***************************************************************************
  *                                                                         *
  *  This program is free software; you can redistribute it and/or modify   *
  *  it under the terms of the GNU General Public License as published by   *
  *  the Free Software Foundation; either version 2 of the License, or      *
  *  (at your option) any later version.                                    *
  *                                                                         *
  *  This program is distributed in the hope that it will be useful,        *
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of         *
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the          *
  *  GNU General Public License for more details.                           *
  *                                                                         *
  *   You should have received a copy of the GNU General Public License     *
  *   along with this program; if not, write to the Free Software           *
  *   Foundation, Inc., 51 Franklin Street, Fifth Floor,                    *
  *   Boston, MA  02110-1301  USA                                           *
  *                                                                         *
  ***************************************************************************/
 
 #include "Matrix.h"
 #include "MatrixPrivate.h"
 #include "matrixcommands.h"
 #include "backend/matrix/MatrixModel.h"
 #include "backend/core/Folder.h"
 #include "backend/lib/commandtemplates.h"
 #include "backend/lib/XmlStreamReader.h"
 #include "commonfrontend/matrix/MatrixView.h"
 #include "kdefrontend/spreadsheet/ExportSpreadsheetDialog.h"
 
 #include <QHeaderView>
 #include <QPrinter>
 #include <QPrintDialog>
 #include <QPrintPreviewDialog>
 
 #include <KConfig>
 #include <KConfigGroup>
 #include <KLocalizedString>
 
 /*!
 	This class manages matrix based data (i.e., mathematically
 	a MxN matrix with M rows, N columns). This data is typically
 	used to for 3D plots.
 
 	The values of the matrix are stored as generic values. Each column
 	of the matrix is stored in a QVector<T> objects.
 
 	\ingroup backend
 */
 Matrix::Matrix(int rows, int cols, const QString& name, const AbstractColumn::ColumnMode mode)
 	: AbstractDataSource(name), d(new MatrixPrivate(this, mode)), m_model(nullptr), m_view(nullptr) {
 
 	//set initial number of rows and columns
 	appendColumns(cols);
 	appendRows(rows);
 
 	init();
 }
 
 Matrix::Matrix(const QString& name, bool loading, const AbstractColumn::ColumnMode mode)
 	: AbstractDataSource(name), d(new MatrixPrivate(this, mode)), m_model(nullptr), m_view(nullptr) {
 
 	if (!loading)
 		init();
 }
 
 Matrix::~Matrix() {
 	delete d;
 }
 
 void Matrix::init() {
 	KConfig config;
 	KConfigGroup group = config.group("Matrix");
 
 	//matrix dimension
 	int rows = group.readEntry("RowCount", 10);
 	int cols = group.readEntry("ColumnCount", 10);
 	appendRows(rows);
 	appendColumns(cols);
 
 	//mapping to logical x- and y-coordinates
 	d->xStart = group.readEntry("XStart", 0.0);
 	d->xEnd = group.readEntry("XEnd", 1.0);
 	d->yStart = group.readEntry("YStart", 0.0);
 	d->yEnd = group.readEntry("YEnd", 1.0);
 
 	//format
 	QByteArray formatba = group.readEntry("NumericFormat", "f").toLatin1();
 	d->numericFormat = *formatba.data();
 	d->precision = group.readEntry("Precision", 3);
 	d->headerFormat = (Matrix::HeaderFormat)group.readEntry("HeaderFormat", (int)Matrix::HeaderRowsColumns);
 }
 
 /*!
   Returns an icon to be used for decorating my views.
   */
 QIcon Matrix::icon() const {
 	return QIcon::fromTheme("labplot-matrix");
 }
 
 /*!
   Returns a new context menu. The caller takes ownership of the menu.
 */
 QMenu* Matrix::createContextMenu() {
 	QMenu* menu = AbstractPart::createContextMenu();
 	emit requestProjectContextMenu(menu);
 	return menu;
 }
 
 QWidget* Matrix::view() const {
 	if (!m_partView) {
 		m_view= new MatrixView(const_cast<Matrix*>(this));
 		m_partView = m_view;
 		m_model = m_view->model();
 	}
 	return m_partView;
 }
 
 bool Matrix::exportView() const {
 	auto* dlg = new ExportSpreadsheetDialog(m_view);
 	dlg->setFileName(name());
 	dlg->setMatrixMode(true);
 
 	//TODO FITS filter to decide if it can be exported to both
 	dlg->setExportTo(QStringList() << i18n("FITS image") << i18n("FITS table"));
 	if (m_view->selectedColumnCount() == 0) {
 		dlg->setExportSelection(false);
 	}
 
 	bool ret;
 	if ( (ret = (dlg->exec() == QDialog::Accepted)) ) {
 		const QString path = dlg->path();
 		WAIT_CURSOR;
 
 		if (dlg->format() == ExportSpreadsheetDialog::LaTeX) {
 			const bool verticalHeader = dlg->matrixVerticalHeader();
 			const bool horizontalHeader = dlg->matrixHorizontalHeader();
 			const bool latexHeader = dlg->exportHeader();
 			const bool gridLines = dlg->gridLines();
 			const bool entire = dlg->entireSpreadheet();
 			const bool captions = dlg->captions();
 			m_view->exportToLaTeX(path, verticalHeader, horizontalHeader,
 				latexHeader, gridLines, entire, captions);
 		} else if (dlg->format() == ExportSpreadsheetDialog::FITS) {
 			const int exportTo = dlg->exportToFits();
 			m_view->exportToFits(path, exportTo );
 		} else {
 			const QString separator = dlg->separator();
 			const QLocale::Language format = dlg->numberFormat();
 			m_view->exportToFile(path, separator, format);
 		}
 		RESET_CURSOR;
     	}
 	delete dlg;
 
 	return ret;
 }
 
 bool Matrix::printView() {
 	QPrinter printer;
 	auto* dlg = new QPrintDialog(&printer, m_view);
 	bool ret;
 	dlg->setWindowTitle(i18nc("@title:window", "Print Matrix"));
 	if ( (ret = (dlg->exec() == QDialog::Accepted)) )
 		m_view->print(&printer);
 
 	delete dlg;
 
 	return ret;
 }
 
 bool Matrix::printPreview() const {
 	QPrintPreviewDialog* dlg = new QPrintPreviewDialog(m_view);
 	connect(dlg, &QPrintPreviewDialog::paintRequested, m_view, &MatrixView::print);
 	return dlg->exec();
 }
 
 //##############################################################################
 //##########################  getter methods  ##################################
 //##############################################################################
 void* Matrix::data() const {
 	return d->data;
 }
 
 BASIC_D_READER_IMPL(Matrix, AbstractColumn::ColumnMode, mode, mode)
 BASIC_D_READER_IMPL(Matrix, int, rowCount, rowCount)
 BASIC_D_READER_IMPL(Matrix, int, columnCount, columnCount)
 BASIC_D_READER_IMPL(Matrix, double, xStart, xStart)
 BASIC_D_READER_IMPL(Matrix, double, xEnd, xEnd)
 BASIC_D_READER_IMPL(Matrix, double, yStart, yStart)
 BASIC_D_READER_IMPL(Matrix, double, yEnd, yEnd)
 BASIC_D_READER_IMPL(Matrix, char, numericFormat, numericFormat)
 BASIC_D_READER_IMPL(Matrix, int, precision, precision)
 BASIC_D_READER_IMPL(Matrix, Matrix::HeaderFormat, headerFormat, headerFormat)
 CLASS_D_READER_IMPL(Matrix, QString, formula, formula)
 
 void Matrix::setSuppressDataChangedSignal(bool b) {
 	if (m_model)
 		m_model->setSuppressDataChangedSignal(b);
 }
 
 void Matrix::setChanged() {
 	if (m_model)
 		m_model->setChanged();
 }
 
 //##############################################################################
 //#################  setter methods and undo commands ##########################
 //##############################################################################
 void Matrix::setRowCount(int count) {
 	if (count == d->rowCount)
 		return;
 
 	const int diff = count - d->rowCount;
 	if (diff > 0)
 		appendRows(diff);
 	else if (diff < 0)
 		removeRows(rowCount() + diff, -diff);
 }
 
 void Matrix::setColumnCount(int count) {
 	if (count == d->columnCount)
 		return;
 
 	const int diff = count - columnCount();
 	if (diff > 0)
 		appendColumns(diff);
 	else if (diff < 0)
 		removeColumns(columnCount() + diff, -diff);
 }
 
 STD_SETTER_CMD_IMPL_F_S(Matrix, SetXStart, double, xStart, updateViewHeader)
 void Matrix::setXStart(double xStart) {
 	if (xStart != d->xStart)
 		exec(new MatrixSetXStartCmd(d, xStart, ki18n("%1: x-start changed")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(Matrix, SetXEnd, double, xEnd, updateViewHeader)
 void Matrix::setXEnd(double xEnd) {
 	if (xEnd != d->xEnd)
 		exec(new MatrixSetXEndCmd(d, xEnd, ki18n("%1: x-end changed")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(Matrix, SetYStart, double, yStart, updateViewHeader)
 void Matrix::setYStart(double yStart) {
 	if (yStart != d->yStart)
 		exec(new MatrixSetYStartCmd(d, yStart, ki18n("%1: y-start changed")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(Matrix, SetYEnd, double, yEnd, updateViewHeader)
 void Matrix::setYEnd(double yEnd) {
 	if (yEnd != d->yEnd)
 		exec(new MatrixSetYEndCmd(d, yEnd, ki18n("%1: y-end changed")));
 }
 
 STD_SETTER_CMD_IMPL_S(Matrix, SetNumericFormat, char, numericFormat)
 void Matrix::setNumericFormat(char format) {
 	if (format != d->numericFormat)
 		exec(new MatrixSetNumericFormatCmd(d, format, ki18n("%1: numeric format changed")));
 }
 
 STD_SETTER_CMD_IMPL_S(Matrix, SetPrecision, int, precision)
 void Matrix::setPrecision(int precision) {
 	if (precision != d->precision)
 		exec(new MatrixSetPrecisionCmd(d, precision, ki18n("%1: precision changed")));
 }
 
 //TODO: make this undoable?
 void Matrix::setHeaderFormat(Matrix::HeaderFormat format) {
 	d->headerFormat = format;
 	m_model->updateHeader();
 
 	if (m_view)
 		m_view->resizeHeaders();
 
 	emit headerFormatChanged(format);
 }
 
 //columns
 void Matrix::insertColumns(int before, int count) {
 	if (count < 1 || before < 0 || before > columnCount()) return;
 	WAIT_CURSOR;
 	exec(new MatrixInsertColumnsCmd(d, before, count));
 	RESET_CURSOR;
 }
 
 void Matrix::appendColumns(int count) {
 	insertColumns(columnCount(), count);
 }
 
 void Matrix::removeColumns(int first, int count) {
 	if (count < 1 || first < 0 || first+count > columnCount()) return;
 	WAIT_CURSOR;
 	switch (d->mode) {
 	case AbstractColumn::Numeric:
 		exec(new MatrixRemoveColumnsCmd<double>(d, first, count));
 		break;
 	case AbstractColumn::Text:
 		exec(new MatrixRemoveColumnsCmd<QString>(d, first, count));
 		break;
 	case AbstractColumn::Integer:
 		exec(new MatrixRemoveColumnsCmd<int>(d, first, count));
 		break;
 	case AbstractColumn::Day:
 	case AbstractColumn::Month:
 	case AbstractColumn::DateTime:
 		exec(new MatrixRemoveColumnsCmd<QDateTime>(d, first, count));
 		break;
 	}
 	RESET_CURSOR;
 }
 
 void Matrix::clearColumn(int c) {
 	WAIT_CURSOR;
 	switch (d->mode) {
 	case AbstractColumn::Numeric:
 		exec(new MatrixClearColumnCmd<double>(d, c));
 		break;
 	case AbstractColumn::Text:
 		exec(new MatrixClearColumnCmd<QString>(d, c));
 		break;
 	case AbstractColumn::Integer:
 		exec(new MatrixClearColumnCmd<int>(d, c));
 		break;
 	case AbstractColumn::Day:
 	case AbstractColumn::Month:
 	case AbstractColumn::DateTime:
 		exec(new MatrixClearColumnCmd<QDateTime>(d, c));
 		break;
 	}
 	RESET_CURSOR;
 }
 
 //rows
 void Matrix::insertRows(int before, int count) {
 	if (count < 1 || before < 0 || before > rowCount()) return;
 	WAIT_CURSOR;
 	exec(new MatrixInsertRowsCmd(d, before, count));
 	RESET_CURSOR;
 }
 
 void Matrix::appendRows(int count) {
 	insertRows(rowCount(), count);
 }
 
 void Matrix::removeRows(int first, int count) {
 	if (count < 1 || first < 0 || first+count > rowCount()) return;
 	WAIT_CURSOR;
 	switch (d->mode) {
 	case AbstractColumn::Numeric:
 		exec(new MatrixRemoveRowsCmd<double>(d, first, count));
 		break;
 	case AbstractColumn::Text:
 		exec(new MatrixRemoveRowsCmd<QString>(d, first, count));
 		break;
 	case AbstractColumn::Integer:
 		exec(new MatrixRemoveRowsCmd<int>(d, first, count));
 		break;
 	case AbstractColumn::Day:
 	case AbstractColumn::Month:
 	case AbstractColumn::DateTime:
 		exec(new MatrixRemoveRowsCmd<QDateTime>(d, first, count));
 		break;
 	}
 	RESET_CURSOR;
 }
 
 void Matrix::clearRow(int r) {
 	switch (d->mode) {
 	case AbstractColumn::Numeric:
 		for (int c = 0; c < columnCount(); ++c)
 			exec(new MatrixSetCellValueCmd<double>(d, r, c, 0.0));
 		break;
 	case AbstractColumn::Text:
 		for (int c = 0; c < columnCount(); ++c)
 			exec(new MatrixSetCellValueCmd<QString>(d, r, c, QString()));
 		break;
 	case AbstractColumn::Integer:
 		for (int c = 0; c < columnCount(); ++c)
 			exec(new MatrixSetCellValueCmd<int>(d, r, c, 0));
 		break;
 	case AbstractColumn::Day:
 	case AbstractColumn::Month:
 	case AbstractColumn::DateTime:
 		for (int c = 0; c < columnCount(); ++c)
 			exec(new MatrixSetCellValueCmd<QDateTime>(d, r, c, QDateTime()));
 		break;
 	}
 }
 
 //! Return the value in the given cell (needs explicit instantiation)
 template <typename T>
 T Matrix::cell(int row, int col) const {
 	return d->cell<T>(row, col);
 }
 template double Matrix::cell<double>(int row, int col) const;
 template int Matrix::cell<int>(int row, int col) const;
 template QDateTime Matrix::cell<QDateTime>(int row, int col) const;
 template QString Matrix::cell<QString>(int row, int col) const;
 
 //! Return the text displayed in the given cell (needs explicit instantiation)
 template <typename T>
 QString Matrix::text(int row, int col) {
 	return QLocale().toString(cell<T>(row,col));
 }
 // special cases
 template <>
 QString Matrix::text<double>(int row, int col) {
 	return QLocale().toString(cell<double>(row,col), d->numericFormat, d->precision);
 }
 template <>
 QString Matrix::text<QString>(int row, int col) {
 	return cell<QString>(row,col);
 }
 template QString Matrix::text<int>(int row, int col);
 template QString Matrix::text<QDateTime>(int row, int col);
 
 //! Set the value of the cell (needs explicit instantiation)
 template <typename T>
 void Matrix::setCell(int row, int col, T value) {
 	if(row < 0 || row >= rowCount()) return;
 	if(col < 0 || col >= columnCount()) return;
 	exec(new MatrixSetCellValueCmd<T>(d, row, col, value));
 }
 template void Matrix::setCell<double>(int row, int col, double value);
 template void Matrix::setCell<int>(int row, int col, int value);
 template void Matrix::setCell<QDateTime>(int row, int col, QDateTime value);
 template void Matrix::setCell<QString>(int row, int col, QString value);
 
 void Matrix::clearCell(int row, int col) {
 	switch (d->mode) {
 	case AbstractColumn::Numeric:
 		exec(new MatrixSetCellValueCmd<double>(d, row, col, 0.0));
 		break;
 	case AbstractColumn::Text:
 		exec(new MatrixSetCellValueCmd<QString>(d, row, col, QString()));
 		break;
 	case AbstractColumn::Integer:
 		exec(new MatrixSetCellValueCmd<int>(d, row, col, 0));
 		break;
 	case AbstractColumn::Day:
 	case AbstractColumn::Month:
 	case AbstractColumn::DateTime:
 		exec(new MatrixSetCellValueCmd<QDateTime>(d, row, col, QDateTime()));
 		break;
 	}
 }
 
 void Matrix::setDimensions(int rows, int cols) {
 	if( (rows < 0) || (cols < 0 ) || (rows == rowCount() && cols == columnCount()) )
 		return;
 
 	WAIT_CURSOR;
 	beginMacro(i18n("%1: set matrix size to %2x%3", name(), rows, cols));
 
 	int col_diff = cols - columnCount();
 	if (col_diff > 0)
 		insertColumns(columnCount(), col_diff);
 	else if (col_diff < 0)
 		removeColumns(columnCount() + col_diff, -col_diff);
 
 	int row_diff = rows - rowCount();
 	if(row_diff > 0)
 		appendRows(row_diff);
 	else if (row_diff < 0)
 		removeRows(rowCount() + row_diff, -row_diff);
 
 	endMacro();
 	RESET_CURSOR;
 }
 
 void Matrix::copy(Matrix* other) {
 	WAIT_CURSOR;
 	beginMacro(i18n("%1: copy %2", name(), other->name()));
 
 	int rows = other->rowCount();
 	int columns = other->columnCount();
 	setDimensions(rows, columns);
 
 	for (int i=0; i<rows; i++)
 		setRowHeight(i, other->rowHeight(i));
 
 	for (int i=0; i<columns; i++)
 		setColumnWidth(i, other->columnWidth(i));
 
 	d->suppressDataChange = true;
 	switch (d->mode) {
 	case AbstractColumn::Numeric:
 		for (int i = 0; i < columns; i++)
 			setColumnCells(i, 0, rows-1, other->columnCells<double>(i, 0, rows-1));
 		break;
 	case AbstractColumn::Text:
 		for (int i = 0; i < columns; i++)
 			setColumnCells(i, 0, rows-1, other->columnCells<QString>(i, 0, rows-1));
 		break;
 	case AbstractColumn::Integer:
 		for (int i = 0; i < columns; i++)
 			setColumnCells(i, 0, rows-1, other->columnCells<int>(i, 0, rows-1));
 		break;
 	case AbstractColumn::Day:
 	case AbstractColumn::Month:
 	case AbstractColumn::DateTime:
 		for (int i = 0; i < columns; i++)
 			setColumnCells(i, 0, rows-1, other->columnCells<QDateTime>(i, 0, rows-1));
 		break;
 	}
 
 	setCoordinates(other->xStart(), other->xEnd(), other->yStart(), other->yEnd());
 	setNumericFormat(other->numericFormat());
 	setPrecision(other->precision());
 	d->formula = other->formula();
 	d->suppressDataChange = false;
 	emit dataChanged(0, 0, rows-1, columns-1);
 	if (m_view)
 		m_view->adjustHeaders();
 
 	endMacro();
 	RESET_CURSOR;
 }
 
 //! Duplicate the matrix inside its folder
 void Matrix::duplicate() {
 	Matrix* matrix = new Matrix(rowCount(), columnCount(), name());
 	matrix->copy(this);
 	if (folder())
 		folder()->addChild(matrix);
 }
 
 void Matrix::addRows() {
 	if (!m_view) return;
 	WAIT_CURSOR;
 	int count = m_view->selectedRowCount(false);
 	beginMacro(i18np("%1: add %2 rows", "%1: add %2 rows", name(), count));
 	exec(new MatrixInsertRowsCmd(d, rowCount(), count));
 	endMacro();
 	RESET_CURSOR;
 }
 
 void Matrix::addColumns() {
 	if (!m_view) return;
 	WAIT_CURSOR;
 	int count = m_view->selectedRowCount(false);
 	beginMacro(i18np("%1: add %2 column", "%1: add %2 columns", name(), count));
 	exec(new MatrixInsertColumnsCmd(d, columnCount(), count));
 	endMacro();
 	RESET_CURSOR;
 }
 
 void Matrix::setCoordinates(double x1, double x2, double y1, double y2) {
 	exec(new MatrixSetCoordinatesCmd(d, x1, x2, y1, y2));
 }
 
 void Matrix::setFormula(const QString& formula) {
 	exec(new MatrixSetFormulaCmd(d, formula));
 }
 
 //! This method should only be called by the view.
 /** This method does not change the view, it only changes the
 	* values that are saved when the matrix is saved. The view
 	* has to take care of reading and applying these values */
 void Matrix::setRowHeight(int row, int height) {
 	d->setRowHeight(row, height);
 }
 
 //! This method should only be called by the view.
 /** This method does not change the view, it only changes the
 	* values that are saved when the matrix is saved. The view
 	* has to take care of reading and applying these values */
 void Matrix::setColumnWidth(int col, int width) {
 	d->setColumnWidth(col, width);
 }
 
 int Matrix::rowHeight(int row) const {
 	return d->rowHeight(row);
 }
 
 int Matrix::columnWidth(int col) const {
 	return d->columnWidth(col);
 }
 
 //! Return the values in the given cells as vector
 template <typename T>
 QVector<T> Matrix::columnCells(int col, int first_row, int last_row) {
 	return d->columnCells<T>(col, first_row, last_row);
 }
 
 //! Set the values in the given cells from a type T vector
 template <typename T>
 void Matrix::setColumnCells(int col, int first_row, int last_row, const QVector<T>& values) {
 	WAIT_CURSOR;
 	exec(new MatrixSetColumnCellsCmd<T>(d, col, first_row, last_row, values));
 	RESET_CURSOR;
 }
 
 //! Return the values in the given cells as vector (needs explicit instantiation)
 template <typename T>
 QVector<T> Matrix::rowCells(int row, int first_column, int last_column) {
 	return d->rowCells<T>(row, first_column, last_column);
 }
 template QVector<double> Matrix::rowCells<double>(int row, int first_column, int last_column);
 template QVector<QString> Matrix::rowCells<QString>(int row, int first_column, int last_column);
 template QVector<int> Matrix::rowCells<int>(int row, int first_column, int last_column);
 template QVector<QDateTime> Matrix::rowCells<QDateTime>(int row, int first_column, int last_column);
 
 //! Set the values in the given cells from a type T vector
 template <typename T>
 void Matrix::setRowCells(int row, int first_column, int last_column, const QVector<T>& values) {
 	WAIT_CURSOR;
 	exec(new MatrixSetRowCellsCmd<T>(d, row, first_column, last_column, values));
 	RESET_CURSOR;
 }
 
 void Matrix::setData(void* data) {
 	bool isEmpty = false;
 
 	switch (d->mode) {
 	case AbstractColumn::Numeric:
 		if (static_cast<QVector<QVector<double>>*>(data)->isEmpty())
 			isEmpty = true;
 		break;
 	case AbstractColumn::Text:
 		if (static_cast<QVector<QVector<QString>>*>(data)->isEmpty())
 			isEmpty = true;
 		break;
 	case AbstractColumn::Integer:
 		if (static_cast<QVector<QVector<int>>*>(data)->isEmpty())
 			isEmpty = true;
 		break;
 	case AbstractColumn::Day:
 	case AbstractColumn::Month:
 	case AbstractColumn::DateTime:
 		if (static_cast<QVector<QVector<QDateTime>>*>(data)->isEmpty())
 			isEmpty = true;
 		break;
 	}
 
 	if (!isEmpty)
 		exec(new MatrixReplaceValuesCmd(d, data));
 }
 
 //##############################################################################
 //#########################  Public slots  #####################################
 //##############################################################################
 //! Clear the whole matrix (i.e. reset all cells)
 void Matrix::clear() {
 	WAIT_CURSOR;
 	beginMacro(i18n("%1: clear", name()));
 	switch (d->mode) {
 	case AbstractColumn::Numeric:
 		exec(new MatrixClearCmd<double>(d));
 		break;
 	case AbstractColumn::Text:
 		exec(new MatrixClearCmd<QString>(d));
 		break;
 	case AbstractColumn::Integer:
 		exec(new MatrixClearCmd<int>(d));
 		break;
 	case AbstractColumn::Day:
 	case AbstractColumn::Month:
 	case AbstractColumn::DateTime:
 		exec(new MatrixClearCmd<QDateTime>(d));
 		break;
 	}
 	endMacro();
 	RESET_CURSOR;
 }
 
 void Matrix::transpose() {
 	WAIT_CURSOR;
 	switch (d->mode) {
 	case AbstractColumn::Numeric:
 		exec(new MatrixTransposeCmd<double>(d));
 		break;
 	case AbstractColumn::Text:
 		exec(new MatrixTransposeCmd<QString>(d));
 		break;
 	case AbstractColumn::Integer:
 		exec(new MatrixTransposeCmd<int>(d));
 		break;
 	case AbstractColumn::Day:
 	case AbstractColumn::Month:
 	case AbstractColumn::DateTime:
 		exec(new MatrixTransposeCmd<QDateTime>(d));
 		break;
 	}
 	RESET_CURSOR;
 }
 
 void Matrix::mirrorHorizontally() {
 	WAIT_CURSOR;
 	switch (d->mode) {
 	case AbstractColumn::Numeric:
 		exec(new MatrixMirrorHorizontallyCmd<double>(d));
 		break;
 	case AbstractColumn::Text:
 		exec(new MatrixMirrorHorizontallyCmd<QString>(d));
 		break;
 	case AbstractColumn::Integer:
 		exec(new MatrixMirrorHorizontallyCmd<int>(d));
 		break;
 	case AbstractColumn::Day:
 	case AbstractColumn::Month:
 	case AbstractColumn::DateTime:
 		exec(new MatrixMirrorHorizontallyCmd<QDateTime>(d));
 		break;
 	}
 	RESET_CURSOR;
 }
 
 void Matrix::mirrorVertically() {
 	WAIT_CURSOR;
 	switch (d->mode) {
 	case AbstractColumn::Numeric:
 		exec(new MatrixMirrorVerticallyCmd<double>(d));
 		break;
 	case AbstractColumn::Text:
 		exec(new MatrixMirrorVerticallyCmd<QString>(d));
 		break;
 	case AbstractColumn::Integer:
 		exec(new MatrixMirrorVerticallyCmd<int>(d));
 		break;
 	case AbstractColumn::Day:
 	case AbstractColumn::Month:
 	case AbstractColumn::DateTime:
 		exec(new MatrixMirrorVerticallyCmd<QDateTime>(d));
 		break;
 	}
 	RESET_CURSOR;
 }
 
 //##############################################################################
 //######################  Private implementation ###############################
 //##############################################################################
 
 MatrixPrivate::MatrixPrivate(Matrix* owner, const AbstractColumn::ColumnMode m)
 		: q(owner), data(nullptr), mode(m), rowCount(0), columnCount(0), suppressDataChange(false) {
 
 	switch (mode) {
 	case AbstractColumn::Numeric:
 		data = new QVector<QVector<double>>();
 		break;
 	case AbstractColumn::Text:
 		data = new QVector<QVector<QString>>();
 		break;
 	case AbstractColumn::Month:
 	case AbstractColumn::Day:
 	case AbstractColumn::DateTime:
 		data = new QVector<QVector<QDateTime>>();
 		break;
 	case AbstractColumn::Integer:
 		data = new QVector<QVector<int>>();
 		break;
 	}
 }
 
 MatrixPrivate::~MatrixPrivate() {
 	if (data) {
 		switch (mode) {
 		case AbstractColumn::Numeric:
 			delete static_cast<QVector<QVector<double>>*>(data);
 			break;
 		case AbstractColumn::Text:
 			delete static_cast<QVector<QVector<QString>>*>(data);
 			break;
 		case AbstractColumn::Integer:
 			delete static_cast<QVector<QVector<int>>*>(data);
 			break;
 		case AbstractColumn::Day:
 		case AbstractColumn::Month:
 		case AbstractColumn::DateTime:
 			delete static_cast<QVector<QVector<QDateTime>>*>(data);
 			break;
 		}
 	}
 }
 
 void MatrixPrivate::updateViewHeader() {
 	q->m_view->model()->updateHeader();
 }
 
 /*!
 	Insert \count columns before column number \c before
 */
 void MatrixPrivate::insertColumns(int before, int count) {
 	Q_ASSERT(before >= 0);
 	Q_ASSERT(before <= columnCount);
 
 	emit q->columnsAboutToBeInserted(before, count);
 	switch (mode) {
 	case AbstractColumn::Numeric:
 		for (int i = 0; i < count; i++) {
 			static_cast<QVector<QVector<double>>*>(data)->insert(before+i, QVector<double>(rowCount));
 			columnWidths.insert(before+i, 0);
 		}
 		break;
 	case AbstractColumn::Text:
 		for (int i = 0; i < count; i++) {
 			static_cast<QVector<QVector<QString>>*>(data)->insert(before+i, QVector<QString>(rowCount));
 			columnWidths.insert(before+i, 0);
 		}
 		break;
 	case AbstractColumn::Integer:
 		for (int i = 0; i < count; i++) {
 			static_cast<QVector<QVector<int>>*>(data)->insert(before+i, QVector<int>(rowCount));
 			columnWidths.insert(before+i, 0);
 		}
 		break;
 	case AbstractColumn::Day:
 	case AbstractColumn::Month:
 	case AbstractColumn::DateTime:
 		for (int i = 0; i < count; i++) {
 			static_cast<QVector<QVector<QDateTime>>*>(data)->insert(before+i, QVector<QDateTime>(rowCount));
 			columnWidths.insert(before+i, 0);
 		}
 		break;
 	}
 
 	columnCount += count;
 	emit q->columnsInserted(before, count);
 }
 
 /*!
 	Remove \c count columns starting with column index \c first
 */
 void MatrixPrivate::removeColumns(int first, int count) {
 	emit q->columnsAboutToBeRemoved(first, count);
 	Q_ASSERT(first >= 0);
 	Q_ASSERT(first + count <= columnCount);
 
 	switch (mode) {
 	case AbstractColumn::Numeric:
 		(static_cast<QVector<QVector<double>>*>(data))->remove(first, count);
 		break;
 	case AbstractColumn::Text:
 		(static_cast<QVector<QVector<QString>>*>(data))->remove(first, count);
 		break;
 	case AbstractColumn::Integer:
 		(static_cast<QVector<QVector<int>>*>(data))->remove(first, count);
 		break;
 	case AbstractColumn::Day:
 	case AbstractColumn::Month:
 	case AbstractColumn::DateTime:
 		(static_cast<QVector<QVector<QDateTime>>*>(data))->remove(first, count);
 		break;
 	}
 
 	for (int i = 0; i < count; i++)
 		columnWidths.remove(first);
 	columnCount -= count;
 	emit q->columnsRemoved(first, count);
 }
 
 /*!
 	Insert \c count rows before row with the index \c before
 */
 void MatrixPrivate::insertRows(int before, int count) {
 	emit q->rowsAboutToBeInserted(before, count);
 	Q_ASSERT(before >= 0);
 	Q_ASSERT(before <= rowCount);
 
 	switch (mode) {
 	case AbstractColumn::Numeric:
 		for (int col = 0; col < columnCount; col++)
 			for (int i = 0; i < count; i++)
 				(static_cast<QVector<QVector<double>>*>(data))->operator[](col).insert(before+i, 0.0);
 		break;
 	case AbstractColumn::Text:
 		for (int col = 0; col < columnCount; col++)
 			for (int i = 0; i < count; i++)
 				(static_cast<QVector<QVector<QString>>*>(data))->operator[](col).insert(before+i, QString());
 		break;
 	case AbstractColumn::Integer:
 		for (int col = 0; col < columnCount; col++)
 			for (int i = 0; i < count; i++)
 				(static_cast<QVector<QVector<int>>*>(data))->operator[](col).insert(before+i, 0);
 		break;
 	case AbstractColumn::Day:
 	case AbstractColumn::Month:
 	case AbstractColumn::DateTime:
 		for (int col = 0; col < columnCount; col++)
 			for (int i = 0; i < count; i++)
 				(static_cast<QVector<QVector<QDateTime>>*>(data))->operator[](col).insert(before+i, QDateTime());
 	}
 
 	for(int i=0; i<count; i++)
 		rowHeights.insert(before+i, 0);
 
 	rowCount += count;
 	emit q->rowsInserted(before, count);
 }
 
 /*!
 	Remove \c count columns starting from the column with index \c first
 */
 void MatrixPrivate::removeRows(int first, int count) {
 	emit q->rowsAboutToBeRemoved(first, count);
 	Q_ASSERT(first >= 0);
 	Q_ASSERT(first+count <= rowCount);
 
 	switch (mode) {
 	case AbstractColumn::Numeric:
 		for (int col = 0; col < columnCount; col++)
 			(static_cast<QVector<QVector<double>>*>(data))->operator[](col).remove(first, count);
 		break;
 	case AbstractColumn::Text:
 		for (int col = 0; col < columnCount; col++)
 			(static_cast<QVector<QVector<QString>>*>(data))->operator[](col).remove(first, count);
 		break;
 	case AbstractColumn::Integer:
 		for (int col = 0; col < columnCount; col++)
 			(static_cast<QVector<QVector<int>>*>(data))->operator[](col).remove(first, count);
 		break;
 	case AbstractColumn::Day:
 	case AbstractColumn::Month:
 	case AbstractColumn::DateTime:
 		for (int col = 0; col < columnCount; col++)
 			(static_cast<QVector<QVector<QDateTime>>*>(data))->operator[](col).remove(first, count);
 		break;
 	}
 
 	for (int i = 0; i < count; i++)
 		rowHeights.remove(first);
 
 	rowCount -= count;
 	emit q->rowsRemoved(first, count);
 }
 
 //! Fill column with zeroes
 void MatrixPrivate::clearColumn(int col) {
 	switch (mode) {
 	case AbstractColumn::Numeric:
 		static_cast<QVector<QVector<double>>*>(data)->operator[](col).fill(0.0);
 		break;
 	case AbstractColumn::Text:
 		static_cast<QVector<QVector<QString>>*>(data)->operator[](col).fill(QString());
 		break;
 	case AbstractColumn::Integer:
 		static_cast<QVector<QVector<int>>*>(data)->operator[](col).fill(0);
 		break;
 	case AbstractColumn::Day:
 	case AbstractColumn::Month:
 	case AbstractColumn::DateTime:
 		static_cast<QVector<QVector<QDateTime>>*>(data)->operator[](col).fill(QDateTime());
 		break;
 	}
 
 	if (!suppressDataChange)
 		emit q->dataChanged(0, col, rowCount-1, col);
 }
 
 //##############################################################################
 //##################  Serialization/Deserialization  ###########################
 //##############################################################################
 void Matrix::save(QXmlStreamWriter* writer) const {
 	DEBUG("Matrix::save()");
 	writer->writeStartElement("matrix");
 	writeBasicAttributes(writer);
 	writeCommentElement(writer);
 
 	//formula
 	writer->writeStartElement("formula");
 	writer->writeCharacters(d->formula);
 	writer->writeEndElement();
 
 	//format
 	writer->writeStartElement("format");
 	writer->writeAttribute("mode", QString::number(d->mode));
 	writer->writeAttribute("headerFormat", QString::number(d->headerFormat));
 	writer->writeAttribute("numericFormat", QString(QChar(d->numericFormat)));
 	writer->writeAttribute("precision", QString::number(d->precision));
 	writer->writeEndElement();
 
 	//dimensions
 	writer->writeStartElement("dimension");
 	writer->writeAttribute("columns", QString::number(d->columnCount));
 	writer->writeAttribute("rows", QString::number(d->rowCount));
 	writer->writeAttribute("x_start", QString::number(d->xStart));
 	writer->writeAttribute("x_end", QString::number(d->xEnd));
 	writer->writeAttribute("y_start", QString::number(d->yStart));
 	writer->writeAttribute("y_end", QString::number(d->yEnd));
 	writer->writeEndElement();
 
 	//vector with row heights
 	writer->writeStartElement("row_heights");
 	const char* data = reinterpret_cast<const char*>(d->rowHeights.constData());
 	int size = d->rowHeights.size() * sizeof(int);
 	writer->writeCharacters(QByteArray::fromRawData(data,size).toBase64());
 	writer->writeEndElement();
 
 	//vector with column widths
 	writer->writeStartElement("column_widths");
 	data = reinterpret_cast<const char*>(d->columnWidths.constData());
 	size = d->columnWidths.size()*sizeof(int);
 	writer->writeCharacters(QByteArray::fromRawData(data, size).toBase64());
 	writer->writeEndElement();
 
 	//columns
 	DEBUG("	mode = " << d->mode);
 	switch (d->mode) {
 	case AbstractColumn::Numeric:
 		size = d->rowCount*sizeof(double);
 		for (int i = 0; i < d->columnCount; ++i) {
 			data = reinterpret_cast<const char*>(static_cast<QVector<QVector<double>>*>(d->data)->at(i).constData());
 			writer->writeStartElement("column");
 			writer->writeCharacters(QByteArray::fromRawData(data, size).toBase64());
 			writer->writeEndElement();
 		}
 		break;
 	case AbstractColumn::Text:
 		size = d->rowCount*sizeof(QString);
 		for (int i = 0; i < d->columnCount; ++i) {
 			QDEBUG("	string: " << static_cast<QVector<QVector<QString>>*>(d->data)->at(i));
 			data = reinterpret_cast<const char*>(static_cast<QVector<QVector<QString>>*>(d->data)->at(i).constData());
 			writer->writeStartElement("column");
 			writer->writeCharacters(QByteArray::fromRawData(data, size).toBase64());
 			writer->writeEndElement();
 		}
 		break;
 	case AbstractColumn::Integer:
 		size = d->rowCount*sizeof(int);
 		for (int i = 0; i < d->columnCount; ++i) {
 			data = reinterpret_cast<const char*>(static_cast<QVector<QVector<int>>*>(d->data)->at(i).constData());
 			writer->writeStartElement("column");
 			writer->writeCharacters(QByteArray::fromRawData(data, size).toBase64());
 			writer->writeEndElement();
 		}
 		break;
 	case AbstractColumn::Day:
 	case AbstractColumn::Month:
 	case AbstractColumn::DateTime:
 		size = d->rowCount*sizeof(QDateTime);
 		for (int i = 0; i < d->columnCount; ++i) {
 			data = reinterpret_cast<const char*>(static_cast<QVector<QVector<QDateTime>>*>(d->data)->at(i).constData());
 			writer->writeStartElement("column");
 			writer->writeCharacters(QByteArray::fromRawData(data, size).toBase64());
 			writer->writeEndElement();
 		}
 		break;
 	}
 
 	writer->writeEndElement(); // "matrix"
 }
 
 bool Matrix::load(XmlStreamReader* reader, bool preview) {
 	DEBUG("Matrix::load()");
 	if (!readBasicAttributes(reader))
 		return false;
 
 	KLocalizedString attributeWarning = ki18n("Attribute '%1' missing or empty, default value is used");
 	QXmlStreamAttributes attribs;
 	QString str;
 
 	// read child elements
 	while (!reader->atEnd()) {
 		reader->readNext();
 
 		if (reader->isEndElement() && reader->name() == "matrix")
 			break;
 
 		if (!reader->isStartElement())
 			continue;
 
 		if (reader->name() == "comment") {
 			if (!readCommentElement(reader)) return false;
 		} else if(!preview && reader->name() == "formula") {
 			d->formula = reader->text().toString().trimmed();
 		} else if (!preview && reader->name() == "format") {
 			attribs = reader->attributes();
 
 			str = attribs.value("mode").toString();
 			if(str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("mode").toString());
 			else
 				d->mode = AbstractColumn::ColumnMode(str.toInt());
 
 			str = attribs.value("headerFormat").toString();
 			if(str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("headerFormat").toString());
 			else
 				d->headerFormat = Matrix::HeaderFormat(str.toInt());
 
 			str = attribs.value("numericFormat").toString();
 			if(str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("numericFormat").toString());
 			else {
 				QByteArray formatba = str.toLatin1();
 				d->numericFormat = *formatba.data();
 			}
 
 			str = attribs.value("precision").toString();
 			if(str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("precision").toString());
 			else
 				d->precision = str.toInt();
 
 		} else if (!preview && reader->name() == "dimension") {
 			attribs = reader->attributes();
 
 			str = attribs.value("columns").toString();
 			if(str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("columns").toString());
 			else
 				d->columnCount = str.toInt();
 
 			str = attribs.value("rows").toString();
 			if(str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("rows").toString());
 			else
 				d->rowCount = str.toInt();
 
 			str = attribs.value("x_start").toString();
 			if(str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("x_start").toString());
 			else
 				d->xStart = str.toDouble();
 
 			str = attribs.value("x_end").toString();
 			if(str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("x_end").toString());
 			else
 				d->xEnd = str.toDouble();
 
 			str = attribs.value("y_start").toString();
 			if(str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("y_start").toString());
 			else
 				d->yStart = str.toDouble();
 
 			str = attribs.value("y_end").toString();
 			if(str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("y_end").toString());
 			else
 				d->yEnd = str.toDouble();
 		} else if (!preview && reader->name() == "row_heights") {
 			reader->readNext();
 			QString content = reader->text().toString().trimmed();
 			QByteArray bytes = QByteArray::fromBase64(content.toLatin1());
 			int count = bytes.size()/sizeof(int);
 			d->rowHeights.resize(count);
 			memcpy(d->rowHeights.data(), bytes.data(), count*sizeof(int));
 		} else if (!preview && reader->name() == "column_widths") {
 			reader->readNext();
 			QString content = reader->text().toString().trimmed();
 			QByteArray bytes = QByteArray::fromBase64(content.toLatin1());
 			int count = bytes.size()/sizeof(int);
 			d->columnWidths.resize(count);
 			memcpy(d->columnWidths.data(), bytes.data(), count*sizeof(int));
 		} else if (!preview && reader->name() == "column") {
 			//TODO: parallelize reading of columns?
 			reader->readNext();
 			QString content = reader->text().toString().trimmed();
 			QByteArray bytes = QByteArray::fromBase64(content.toLatin1());
 
 			switch (d->mode) {
 			case AbstractColumn::Numeric: {
 				int count = bytes.size()/sizeof(double);
 				QVector<double> column;
 				column.resize(count);
 				memcpy(column.data(), bytes.data(), count*sizeof(double));
 				static_cast<QVector<QVector<double>>*>(d->data)->append(column);
 				break;
 			}
 			case AbstractColumn::Text: {
 				int count = bytes.size()/sizeof(char);
 				QVector<QString> column;
 				column.resize(count);
 				//TODO: warning (GCC8): writing to an object of type 'class QString' with no trivial copy-assignment; use copy-assignment or copy-initialization instead
-				memcpy(column.data(), bytes.data(), count*sizeof(char));
-				QDEBUG("	string: " << column.data());
+				//memcpy(column.data(), bytes.data(), count*sizeof(QString));
+				//QDEBUG("	string: " << column.data());
 				static_cast<QVector<QVector<QString>>*>(d->data)->append(column);
 				break;
 			}
 			case AbstractColumn::Integer: {
 				int count = bytes.size()/sizeof(int);
 				QVector<int> column;
 				column.resize(count);
 				memcpy(column.data(), bytes.data(), count*sizeof(int));
 				static_cast<QVector<QVector<int>>*>(d->data)->append(column);
 				break;
 			}
 			case AbstractColumn::Day:
 			case AbstractColumn::Month:
 			case AbstractColumn::DateTime: {
 				int count = bytes.size()/sizeof(QDateTime);
 				QVector<QDateTime> column;
 				column.resize(count);
 				//TODO: warning (GCC8): writing to an object of type 'class QDateTime' with no trivial copy-assignment; use copy-assignment or copy-initialization instead
 				//memcpy(column.data(), bytes.data(), count*sizeof(QDateTime));
 				static_cast<QVector<QVector<QDateTime>>*>(d->data)->append(column);
 				break;
 			}
 			}
 		} else { // unknown element
 			reader->raiseWarning(i18n("unknown element '%1'", reader->name().toString()));
 			if (!reader->skipToEndElement())
 				return false;
 		}
 	}
 
 	return true;
 }
 
 //##############################################################################
 //########################  Data Import  #######################################
 //##############################################################################
 int Matrix::prepareImport(QVector<void*>& dataContainer, AbstractFileFilter::ImportMode mode,
 	int actualRows, int actualCols, QStringList colNameList, QVector<AbstractColumn::ColumnMode> columnMode) {
 	QDEBUG("prepareImport() rows =" << actualRows << " cols =" << actualCols);
 	QDEBUG("	column modes = " << columnMode);
 	Q_UNUSED(colNameList);
 	int columnOffset = 0;
 	setUndoAware(false);
 
 	setSuppressDataChangedSignal(true);
 
 	// resize the matrix
 	if (mode == AbstractFileFilter::Replace) {
 		clear();
 		setDimensions(actualRows, actualCols);
 	} else {
 		if (rowCount() < actualRows)
 			setDimensions(actualRows, actualCols);
 		else
 			setDimensions(rowCount(), actualCols);
 	}
 
 	// data() returns a void* which is a pointer to a matrix of any data type (see ColumnPrivate.cpp)
 	dataContainer.resize(actualCols);
 	switch (columnMode[0]) {	// only columnMode[0] is used
 	case AbstractColumn::Numeric:
 		for (int n = 0; n < actualCols; n++) {
 			QVector<double>* vector = &(static_cast<QVector<QVector<double>>*>(data())->operator[](n));
-			vector->reserve(actualRows);
 			vector->resize(actualRows);
 			dataContainer[n] = static_cast<void*>(vector);
 		}
 		d->mode = AbstractColumn::Numeric;
 		break;
 	case AbstractColumn::Integer:
 		for (int n = 0; n < actualCols; n++) {
 			QVector<int>* vector = &(static_cast<QVector<QVector<int>>*>(data())->operator[](n));
-			vector->reserve(actualRows);
 			vector->resize(actualRows);
 			dataContainer[n] = static_cast<void*>(vector);
 		}
 		d->mode = AbstractColumn::Integer;
 		break;
 	case AbstractColumn::Text:
 		for (int n = 0; n < actualCols; n++) {
 			QVector<QString>* vector = &(static_cast<QVector<QVector<QString>>*>(data())->operator[](n));
-			vector->reserve(actualRows);
 			vector->resize(actualRows);
 			dataContainer[n] = static_cast<void*>(vector);
 		}
 		d->mode = AbstractColumn::Text;
 		break;
 	case AbstractColumn::Day:
 	case AbstractColumn::Month:
 	case AbstractColumn::DateTime:
 		for (int n = 0; n < actualCols; n++) {
 			QVector<QDateTime>* vector = &(static_cast<QVector<QVector<QDateTime>>*>(data())->operator[](n));
-			vector->reserve(actualRows);
 			vector->resize(actualRows);
 			dataContainer[n] = static_cast<void*>(vector);
 		}
 		d->mode = AbstractColumn::DateTime;
 		break;
 	}
 
 	return columnOffset;
 }
 
 void Matrix::finalizeImport(int columnOffset, int startColumn, int endColumn, int numRows, const QString& dateTimeFormat, AbstractFileFilter::ImportMode importMode)  {
 	DEBUG("Matrix::finalizeImport()");
 	Q_UNUSED(columnOffset);
 	Q_UNUSED(startColumn);
 	Q_UNUSED(endColumn);
 	Q_UNUSED(numRows);
 	Q_UNUSED(dateTimeFormat);
 	Q_UNUSED(importMode);
 
 	setSuppressDataChangedSignal(false);
 	setChanged();
 	setUndoAware(true);
 	DEBUG("Matrix::finalizeImport() DONE");
 }