17 Dec
2006
17 Dec
'06
11:31 p.m.
On Tue, 5 Dec 2006, Neilen Marais wrote:
Hi
I'm trying to get the DFT of the derivative of a real valued periodic signal. If I have the time domain signal in ts (where one period is stored in ts), I do:
fs = scipy.fftpack.fft(ts) dfs = scipy.fftpack.diff(fs) dts = scipy.fftpack.ifft(dfs)
However dts seems to be almost purely imaginary whereas ts is purely real. I haven't done DFT related stuff for a while, am I misunderstanding completely?
Yes, you can do dts = scipy.fftpack.diff(ts) Pearu