21 Nov
2007
21 Nov
'07
5:55 p.m.
cos^2+sin^2=1
ah!
so, actually the FFT doesn't HAVE to use imaginary numbers....but they are just used because "the complex-number system is two-dimensional and that signals to be analysed are presumed to be two-dimensional. They are decomposable into a sum of circular trajectories"
every day a bit more of this falls into place.