Legacy discrete Fourier transforms (scipy.fftpack)#

Warning

This submodule is now considered legacy, new code should use scipy.fft.

Fast Fourier Transforms (FFTs)#

fft(x[, n, axis, overwrite_x])

Return discrete Fourier transform of real or complex sequence.

ifft(x[, n, axis, overwrite_x])

Return discrete inverse Fourier transform of real or complex sequence.

fft2(x[, shape, axes, overwrite_x])

2-D discrete Fourier transform.

ifft2(x[, shape, axes, overwrite_x])

2-D discrete inverse Fourier transform of real or complex sequence.

fftn(x[, shape, axes, overwrite_x])

Return multidimensional discrete Fourier transform.

ifftn(x[, shape, axes, overwrite_x])

Return inverse multidimensional discrete Fourier transform.

rfft(x[, n, axis, overwrite_x])

Discrete Fourier transform of a real sequence.

irfft(x[, n, axis, overwrite_x])

Return inverse discrete Fourier transform of real sequence x.

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, shape, axes, norm, overwrite_x])

Return multidimensional Discrete Cosine Transform along the specified axes.

idctn(x[, type, shape, axes, norm, overwrite_x])

Return multidimensional 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, shape, axes, norm, overwrite_x])

Return multidimensional Discrete Sine Transform along the specified axes.

idstn(x[, type, shape, axes, norm, overwrite_x])

Return multidimensional Discrete Sine Transform along the specified axes.

Differential and pseudo-differential operators#

diff(x[, order, period, _cache])

Return kth derivative (or integral) of a periodic sequence x.

tilbert(x, h[, period, _cache])

Return h-Tilbert transform of a periodic sequence x.

itilbert(x, h[, period, _cache])

Return inverse h-Tilbert transform of a periodic sequence x.

hilbert(x[, _cache])

Return Hilbert transform of a periodic sequence x.

ihilbert(x)

Return inverse Hilbert transform of a periodic sequence x.

cs_diff(x, a, b[, period, _cache])

Return (a,b)-cosh/sinh pseudo-derivative of a periodic sequence.

sc_diff(x, a, b[, period, _cache])

Return (a,b)-sinh/cosh pseudo-derivative of a periodic sequence x.

ss_diff(x, a, b[, period, _cache])

Return (a,b)-sinh/sinh pseudo-derivative of a periodic sequence x.

cc_diff(x, a, b[, period, _cache])

Return (a,b)-cosh/cosh pseudo-derivative of a periodic sequence.

shift(x, a[, period, _cache])

Shift periodic sequence x by a: y(u) = x(u+a).

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])

Return the Discrete Fourier Transform sample frequencies.

rfftfreq(n[, d])

DFT sample frequencies (for usage with rfft, irfft).

next_fast_len(target)

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

Note that fftshift, ifftshift and fftfreq are numpy functions exposed by fftpack; importing them from numpy should be preferred.

Convolutions (scipy.fftpack.convolve)#

convolve(x,omega,[swap_real_imag,overwrite_x])

Wrapper for convolve.

convolve_z(x,omega_real,omega_imag,[overwrite_x])

Wrapper for convolve_z.

init_convolution_kernel(...)

Wrapper for init_convolution_kernel.

destroy_convolve_cache