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# numpy.fft.ifft

`numpy.fft.``ifft`(a, n=None, axis=-1)

  Compute the one-dimensonal inverse fft along an axis.

  Return the n point inverse discrete Fourier transform of a. The length n defaults to the length of a. If n is larger than the length of a, then a will be zero-padded to make up the difference. If n is smaller than the length of a, then a will be truncated to reduce its size.

  Parameters: | a : array_like Input array. n : int, optional Length of the fft. axis : int, optional Axis over which to compute the inverse fft.

  See also

  `fft`

  Notes

  The input array is expected to be packed the same way as the output of fft, as discussed in the fft documentation.

  This is the inverse of fft: ifft(fft(a)) == a within numerical accuracy.

  This is most efficient for n a power of two. This also stores a cache of working memory for different sizes of fft’s, so you could theoretically run into memory problems if you call this too many times with too many different n values.

### Navigation

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- NumPy v1.3 Manual (DRAFT) »
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