irfft#

pynlo.utility.fft.irfft(x, fsc=1.0, n=None, axis=-1)[source]#

Use MKL to perform a 1D IFFT of the input array along the given axis. The input is assumed to contain only positive frequencies, and the output is always real.

If n is not given the length of the transformed axis is 2*(m-1), where m is the length of the transformed axis of the input. To get an odd number of output points, n must be specified.

Parameters:

xarray_like: Input array, can be complex.
fscfloat, optional: The forward transform scale factor. Internally, this function sets the reverse transform scale factor as 1/(n*fsc). The default is 1.0.
nint, optional: Length of the transformed axis of the output. For n output points, n//2+1 input points are necessary. If the input is longer than this, it is cropped. If it is shorter than this, it is padded with zeros.
axisint, optional: Axis over which to compute the inverse FFT. The default is the last axis.

Returns:

ndarray: The transformed array.