Hi
I need to compute the fft of an image A with dimension (Nx,Ny) and are not sure
on how to compute the wavenumber.
I have done like that but i am not sure i am computing the wavenumber in the
correct way..can someone help?
sara
image.plot(x,y,A)
dx = diff(x)[1]
dy = diff(y)[1]
## This is equivalent to what the matlab fftshift function does
fzs = fft(A)
Fzs = fftshift2D(fzs)/(Nx*Ny);
## compute the wave number for the shifted fourier transform
k = seq(-pi/dx,pi/dx,length.out=Nx);
l = seq(-pi/dy,pi/dy,length.out=Ny);
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