FFTGUI Demonstration of Finite Fourier Transform. FFTGUI(y) plots real(y), imag(y), real(fft(y)) and imag(fft(y)). FFTGUI, without any arguments, uses y = zeros(1,32). When any point is moved with the mouse, the other plots respond. Inspired by Java applet by Dave Hale, Stanford Exploration Project, http://sepwww.stanford.edu/oldsep/hale/FftLab.html