How to compute FFT?
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Hi there
I just would like to ask, if there is an efficient way to compute the FFT without using the built-in method? Because i need the code on something else, so i found a code to compute it, however, it takes a very long time, so i would highly appreciate it if you could suggest me any way to make it more faster? thank you in advance
function z=Fast_Fourier_Transform(x,nfft)
%
j=sqrt(-1);
N=length(x);
z=zeros(1,nfft);
Sum=0;
for k=1:nfft
for jj=1:N
Sum=Sum+x(jj)*exp(-2*pi*j*(jj-1)*(k-1)/nfft);
end
z(k)=Sum;
Sum=0;% Reset
end
return
回答（1 个）
John D'Errico
2016-5-10
0 个投票
Sorry. You are never going to make that code run as fast as FFT, or even reasonably close to it.
You can always look for a C based FFT code. There must be lots of them around.
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