On Sunday, 15 September 2013 at 20:58:54 UTC, Kadir Erdem Demir
wrote:
I believe I am well aware of the things which are explained in
the link. There is a sentence in link which says : "The first
bin in the FFT is DC (0 Hz), the second bin is Fs / N, where Fs
is the sample rate and N is the size of the FFT."
My question how can I determine the "N" which is the size of
FFT ?
In fftw library one can define N like :
fftw_create_plan(N, FFTW_FORWARD, FFTW_ESTIMATE);
In D do we have a way to do that ?
I am not aware of the details of that particular FFTW function,
but mathematically, the result of the Fourier transform of a
given vector is _always_ a vector of the same size. Thus, I guess
using FFTW in that way just amounts to the equivalent of
fft(timeDomainAmplitudeVal[0 .. N]).
David
