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# numpy.fft.irfft

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

  Compute the one-dimensional inverse fft for real input.

  Parameters: | a : array Input array with real data type. n : int Length of the fft. axis : int Axis over which to compute the fft.

  See also

  `rfft`

  Notes

  Return the real valued n point inverse discrete Fourier transform of a, where a contains the nonnegative frequency terms of a Hermite-symmetric sequence. n is the length of the result, not the input. If n is not supplied, the default is 2*(len(a)-1). If you want the length of the result to be odd, you have to say so.

  If you specify an n such that a must be zero-padded or truncated, the extra/removed values will be added/removed at high frequencies. One can thus resample a series to m points via Fourier interpolation by: a_resamp = irfft(rfft(a), m).

  Within numerical accuracy `irfft` is the inverse of `rfft`:

      irfft(rfft(a), len(a)) == a

### Navigation

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- NumPy v1.3 Manual (DRAFT) »
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