idft.m

来自「linear time－frequency toolbox」· M 代码 · 共 28 行

function f=idft(f,N,dim)
%IDFT  Inverse DFT
%   Usage: f=idft(f);
%          f=idft(f,N,dim);
%
%   This function computes a normalized inverse discrete Fourier transform.
%   This is nothing but a scaled version of the output from IFFT. The
%   function takes exactly the same arguments as IFFT. See the help on IFFT
%   for a throurough description.
%
%   SEE ALSO:  DFT

error(nargchk(1,3,nargin));

if nargin<3
  dim=1;
end;

if nargin==1
  N=size(f,1);
end;

if isempty(N)
  N=size(f,dim);
end;

f=ifft(f,N,dim)*sqrt(N);