fft.irfft2(a, s=None, axes=(-2,-1), norm=None, out=None)
Computes the inverse of
.
Parameters:aarray_likeThe input array
ssequence of ints, optionalShape of the real output to the inverse FFT.
Changed in version 2.0: If it is -1, the whole input is used (no padding/trimming).
Deprecated since version 2.0: If s is not None, axes must not be None either.
Deprecated since version 2.0: s must contain only int s, not None values. None values currently mean that the default value for n is used in the corresponding 1-D transform, but this behaviour is deprecated.
axessequence of ints, optionalThe axes over which to compute the inverse fft. Default: (-2,-1), the last two axes.
Deprecated since version 2.0: If s is specified, the corresponding axes to be transformed must not be None.
norm{“backward”, “ortho”, “forward”}, optionalNormalization mode (see
). Default is “backward”. Indicates which direction of the forward/backward pair of transforms is scaled and with what normalization factor.
Added in version 1.20.0: The “backward”, “forward” values were added.
outndarray, optionalIf provided, the result will be placed in this array. It should be of the appropriate shape and dtype for the last transformation.
Added in version 2.0.0.
Returns:outndarrayThe result of the inverse real 2-D FFT.
See also
The forward two-dimensional FFT of real input, of which
is the inverse.
The one-dimensional FFT for real input.
The inverse of the one-dimensional FFT of real input.
Compute the inverse of the N-dimensional FFT of real input.
Notes
This is really
with different defaults. For more details see
.
Examples
>>> importnumpyasnp>>> a=np.mgrid[:5,:5][0]>>> A=np.fft.rfft2(a)>>> np.fft.irfft2(A,s=a.shape)array([[0., 0., 0., 0., 0.], [1., 1., 1., 1., 1.], [2., 2., 2., 2., 2.], [3., 3., 3., 3., 3.], [4., 4., 4., 4., 4.]])