| MATLAB Function Reference | Search Help Desk |
| ifft2 | Examples See Also |
Inverse two-dimensional fast Fourier transform
Syntax
Y = ifft2(X) Y = ifft2(X,m,n)
Description
Y = ifft2(X)
returns the two-dimensional inverse fast Fourier transform of matrix X.
Y = ifft2(X,m,n)
returns the m-by-n inverse fast Fourier transform of matrix X.
Examples
For anyX, ifft2(fft2(X)) equals X to within roundoff error. If X is real, ifft2(fft2(X)) may have small imaginary parts.
Algorithm
The algorithm forifft2(X) is the same as the algorithm for fft2(X), 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 2 and slowest when they are large primes.
See Also
dftmtx and freqz in the Signal Processing Toolbox, and:
fft2, fftshift, ifft