Re: Any FFT expert around?

[peter]

> Hi Oxy,
>
> The frequency vector for FFT should go from DC as bin 1 to slightly less
> than Fs in the last bin (Fs - Fs/N where N is the number of FFT points).
>
> If you want to plot this as a range from -Fs/2 to +Fs/2 (minus the same
> fraction) you can do this, but in this case you should use the fftshift
> function as follows:
>
> freqsig = fftshift(fft(tdsig));
>
> Also, make sure you are intending to plot the REAL part of the FFT only (I
> believe that is the default behavior for how you are executing the plot).
>

More blatant promotion: LTFAT has the "plotfft" and "plotfftreal"
functions for visualing coefficients coming from fft operations:

http://ltfat.sourceforge.net/doc/fourier/plotfft.php
http://ltfat.sourceforge.net/doc/fourier/plotfftreal.php

Cheers,
Peter.