Discrete Fourier transforms (scipy.fft)#

Fast Fourier Transforms (FFTs)#

fft(x[, n, axis, norm, overwrite_x, ...])

Compute the 1-D discrete Fourier Transform.

ifft(x[, n, axis, norm, overwrite_x, ...])

Compute the 1-D inverse discrete Fourier Transform.

fft2(x[, s, axes, norm, overwrite_x, ...])

Compute the 2-D discrete Fourier Transform

ifft2(x[, s, axes, norm, overwrite_x, ...])

Compute the 2-D inverse discrete Fourier Transform.

fftn(x[, s, axes, norm, overwrite_x, ...])

Compute the N-D discrete Fourier Transform.

ifftn(x[, s, axes, norm, overwrite_x, ...])

Compute the N-D inverse discrete Fourier Transform.

rfft(x[, n, axis, norm, overwrite_x, ...])

Compute the 1-D discrete Fourier Transform for real input.

irfft(x[, n, axis, norm, overwrite_x, ...])

Computes the inverse of rfft.

rfft2(x[, s, axes, norm, overwrite_x, ...])

Compute the 2-D FFT of a real array.

irfft2(x[, s, axes, norm, overwrite_x, ...])

Computes the inverse of rfft2

rfftn(x[, s, axes, norm, overwrite_x, ...])

Compute the N-D discrete Fourier Transform for real input.

irfftn(x[, s, axes, norm, overwrite_x, ...])

Computes the inverse of rfftn

hfft(x[, n, axis, norm, overwrite_x, ...])

Compute the FFT of a signal that has Hermitian symmetry, i.e., a real spectrum.

ihfft(x[, n, axis, norm, overwrite_x, ...])

Compute the inverse FFT of a signal that has Hermitian symmetry.

hfft2(x[, s, axes, norm, overwrite_x, ...])

Compute the 2-D FFT of a Hermitian complex array.

ihfft2(x[, s, axes, norm, overwrite_x, ...])

Compute the 2-D inverse FFT of a real spectrum.

hfftn(x[, s, axes, norm, overwrite_x, ...])

Compute the N-D FFT of Hermitian symmetric complex input, i.e., a signal with a real spectrum.

ihfftn(x[, s, axes, norm, overwrite_x, ...])

Compute the N-D inverse discrete Fourier Transform for a real spectrum.

Discrete Sin and Cosine Transforms (DST and DCT)#

dct(x[, type, n, axis, norm, overwrite_x, ...])

Return the Discrete Cosine Transform of arbitrary type sequence x.

idct(x[, type, n, axis, norm, overwrite_x, ...])

Return the Inverse Discrete Cosine Transform of an arbitrary type sequence.

dctn(x[, type, s, axes, norm, overwrite_x, ...])

Return multidimensional Discrete Cosine Transform along the specified axes.

idctn(x[, type, s, axes, norm, overwrite_x, ...])

Return multidimensional Inverse Discrete Cosine Transform along the specified axes.

dst(x[, type, n, axis, norm, overwrite_x, ...])

Return the Discrete Sine Transform of arbitrary type sequence x.

idst(x[, type, n, axis, norm, overwrite_x, ...])

Return the Inverse Discrete Sine Transform of an arbitrary type sequence.

dstn(x[, type, s, axes, norm, overwrite_x, ...])

Return multidimensional Discrete Sine Transform along the specified axes.

idstn(x[, type, s, axes, norm, overwrite_x, ...])

Return multidimensional Inverse Discrete Sine Transform along the specified axes.

Fast Hankel Transforms#

fht(a, dln, mu[, offset, bias])

Compute the fast Hankel transform.

ifht(A, dln, mu[, offset, bias])

Compute the inverse fast Hankel transform.

Helper functions#

fftshift(x[, axes])

Shift the zero-frequency component to the center of the spectrum.

ifftshift(x[, axes])

The inverse of fftshift.

fftfreq(n[, d, xp, device])

Return the Discrete Fourier Transform sample frequencies.

rfftfreq(n[, d, xp, device])

Return the Discrete Fourier Transform sample frequencies (for usage with rfft, irfft).

fhtoffset(dln, mu[, initial, bias])

Return optimal offset for a fast Hankel transform.

next_fast_len(target[, real])

Find the next fast size of input data to fft, for zero-padding, etc.

set_workers(workers)

Context manager for the default number of workers used in scipy.fft

get_workers()

Returns the default number of workers within the current context

Backend control#

set_backend(backend[, coerce, only])

Context manager to set the backend within a fixed scope.

skip_backend(backend)

Context manager to skip a backend within a fixed scope.

set_global_backend(backend[, coerce, only, ...])

Sets the global fft backend

register_backend(backend)

Register a backend for permanent use.