Digital signal processing magic

So many signal processing calculations and several filter design options.It is used as easy and as simple as a pocket calculator yet can do very complex and useful operations.It has the following options: >Discrete fourier transform and its inverse >Correlation and convolution >Z transform and its inverse >FIR filters >Bonus intelligent IIR filters design which attempts to find iir filter parameters. It is useful for a very wide engineering and science community in design, research, and education.