ifft(x, n=None, axis=-1, overwrite_x=False)¶
Return discrete inverse Fourier transform of real or complex sequence.
The returned complex array contains
y(0), y(1),..., y(n-1)where
y(j) = (x * exp(2*pi*sqrt(-1)*j*np.arange(n)/n)).mean().
x : array_like
Transformed data to invert.
n : int, optional
Length of the inverse Fourier transform. If
n < x.shape[axis], x is truncated. If
n > x.shape[axis], x is zero-padded. The default results in
n = x.shape[axis].
axis : int, optional
Axis along which the ifft’s are computed; the default is over the last axis (i.e.,
overwrite_x : bool, optional
If True, the contents of x can be destroyed; the default is False.
ifft : ndarray of floats
The inverse discrete Fourier transform.
- Forward FFT
Both single and double precision routines are implemented. Half precision inputs will be converted to single precision. Non floating-point inputs will be converted to double precision. Long-double precision inputs are not supported.
This function is most efficient when n is a power of two, and least efficient when n is prime.
If the data type of x is real, a “real IFFT” algorithm is automatically used, which roughly halves the computation time.