cupynumeric.fft.ifft#
- cupynumeric.fft.ifft( ) ndarray #
Compute the one-dimensional inverse discrete Fourier Transform.
This function computes the inverse of the one-dimensional n-point discrete Fourier transform computed by fft. In other words,
ifft(fft(a)) == a
to within numerical accuracy. For a general description of the algorithm and definitions, see numpy.fft.The input should be ordered in the same way as is returned by fft, i.e.,
a[0]
should contain the zero frequency term,a[1:n//2]
should contain the positive-frequency terms,a[n//2 + 1:]
should contain the negative-frequency terms, in increasing order starting from the most negative frequency.
For an even number of input points,
A[n//2]
represents the sum of the values at the positive and negative Nyquist frequencies, as the two are aliased together. See numpy.fft for details.- Parameters:
a (array_like) – Input array, can be complex.
n (int, optional) – Length of the transformed axis of the output. If n is smaller than the length of the input, the input is cropped. If it is larger, the input is padded with zeros. If n is not given, the length of the input along the axis specified by axis is used. See notes about padding issues.
axis (int, optional) – Axis over which to compute the inverse DFT. If not given, the last axis is used.
norm (
{"backward", "ortho", "forward"}
, optional) – Normalization mode (see numpy.fft). Default is “backward”. Indicates which direction of the forward/backward pair of transforms is scaled and with what normalization factor.
- Returns:
out – The truncated or zero-padded input, transformed along the axis indicated by axis, or the last one if axis is not specified.
- Return type:
complex ndarray
Notes
This is really ifftn with different defaults. For more details see ifftn. Multi-GPU usage is limited to data parallel axis-wise batching.
See also
- Availability:
Multiple GPUs