Implement analysis functions
* Smooth
* Interpolation
* Calculations
** Differences (forward, backward, center)
** Sum/Integration
* Transforms
** Fourier Transform (direction, normalization, window, etc.)
** Correlation
** Convolution/Deconvolution
* Misc
** Wiener, Kalman filter
** Periodigram (see kst)
** Cross spectrum (see kst)
http://www.originlab.com/doc/Origin-Help/Smooth-Algorithm
https://kst-plot.kde.org/kst1/handbook/plugins-vector-processing.html