dft¶

discrete Fourier transform

Calling Sequence¶

[xf]=dft(x,flag);

:x input vector : :flag indicates dft (flag=-1) or idft (flag=1) : :xf output vector :

Function which computes dft of vector x.

n=8;omega = `exp`_(-2*%pi*%i/n);
j=0:n-1;F=omega.^(j'*j);  //Fourier matrix
x=1:8;x=x(:);
F*x
`fft`_(x,-1)
dft(x,-1)
`inv`_(F)*x
`fft`_(x,1)
dft(x,1)