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| ifft2 | See Also |
Two-dimensional inverse fast Fourier transform.
Syntax
Y = ifft2(X) Y = ifft2(X,m,n)
Description
Y = ifft2(X)
returns the two-dimensional inverse fast Fourier transform (FFT) of the array X. If X is a vector, Y has the same orientation as X.
Y = ifft2(X,m,n)
truncates or zero pads X, if necessary, to create an m-by-n array before performing the inverse FFT. The result Y is also m-by-n.
For any X, ifft2(fft2(X)) equals X to within roundoff error. If X is real, ifft2(fft2(X)) may have small imaginary parts.
The ifft2 function is part of the standard MATLAB language.
Algorithm
The algorithm forifft2 is the same as that for fft2, except for a sign change and scale factors of [m n]= size(X). The execution time is fastest when m and n are powers of two and slowest when they are large primes.
See Also
fft |
One-dimensional fast Fourier transform. |
fft2 |
Two-dimensional fast Fourier transform. |
fftn |
N-dimensional fast Fourier transform (see the online MATLAB Function Reference). |
fftshift |
Rearrange the outputs of fft and fft2. |
ifft |
One-dimensional inverse fast Fourier transform. |
ifftn |
N-dimensional inverse fast Fourier transform (see the online MATLAB Function Reference). |