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ifftn | See Also |
Inverse multidimensional fast Fourier transform
Y = ifftn(X)
Y = ifftn(X,
siz)
Y = ifftn(X)
performs the N-dimensional inverse fast Fourier transform. The result Y
is the same size as X
.
Y = ifftn(X,siz)
pads X
with zeros, or truncates X
, to create a multidimensional array of size siz
before performing the inverse transform. The size of the result Y
is siz
.
For any X
, ifftn(fftn(X))
equals X
within roundoff error. If X
is real, ifftn(fftn(X))
may have small imaginary parts.
ifftn(X)
is equivalent to
Y = X; for p = 1:length(size(X)) Y = ifft(Y,[],p); endThis computes in-place the one-dimensional inverse fast Fourier transform along each dimension of
X
. The time required to compute ifftn(X)
depends strongly on the number of prime factors of the dimensions of X
. It is fastest when all of the dimensions are powers of 2.
fft
One-dimensional fast Fourier transform
fft2
Two-dimensional fast Fourier transform
fftn
Multidimensional fast Fourier transform