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scipy.fftpack

The package scipy.fftpack does two things: fast Fourier transforms, and differentiation and integration of periodic sequences.

Fast Fourier Transforms

The fft() function can be used by importing scipy, ie import scipy * However, other functions such as fft2 and the helper functions require the import of fftpack explicitly.

fft(a)

performs an Fourier transform on the array a and returns a complex array

ifft()
Inverse of fft
fftn()
Multi-dimensional FFT
ifftn()
Inverse of fftn
fft2()
2D FFT
ifft2()
Inverse of fft2
rfft()
FFT of real periodic sequences
irfft()
Inverse of rfft

Differential and pseudo-differential operators

Helper functions

The helper functions have to be imported explicitly to be able to use them. That is import scipy * is not enough, import scipy.fftpack is required

fftshift()
Shift zero-frequency component to the centre of the spectrum
ifftshift()
Inverse of fftshift
dftfreq()
rfftfreq()

Extension modules

SciPy: SciPyPackages/Fftpack (last edited 2015-10-24 17:48:23 by anonymous)