Skip to main content

Python interface to the FFTW library

Project description

Compute fast Fourier transforms in Python.


The following code snippet shows how to compute the forward Fourier transform of an arbitrary array of 64 samples:

>>> from fftw.fftw import Plan
>>> import numpy
>>> input_array = numpy.arange(64, dtype=numpy.complex)
>>> plan = Plan(input_array, output_array=numpy.empty_like(input_array))
>>> result_array = plan()

>>> print(input_array)
[  0.+0.j   1.+0.j   2.+0.j   3.+0.j   4.+0.j   5.+0.j   6.+0.j   7.+0.j
   8.+0.j   9.+0.j  10.+0.j  11.+0.j  12.+0.j  13.+0.j  14.+0.j  15.+0.j
  16.+0.j  17.+0.j  18.+0.j  19.+0.j  20.+0.j  21.+0.j  22.+0.j  23.+0.j
  24.+0.j  25.+0.j  26.+0.j  27.+0.j  28.+0.j  29.+0.j  30.+0.j  31.+0.j
  32.+0.j  33.+0.j  34.+0.j  35.+0.j  36.+0.j  37.+0.j  38.+0.j  39.+0.j
  40.+0.j  41.+0.j  42.+0.j  43.+0.j  44.+0.j  45.+0.j  46.+0.j  47.+0.j
  48.+0.j  49.+0.j  50.+0.j  51.+0.j  52.+0.j  53.+0.j  54.+0.j  55.+0.j
  56.+0.j  57.+0.j  58.+0.j  59.+0.j  60.+0.j  61.+0.j  62.+0.j  63.+0.j]

>>> print(result_array)
[ 2016.  +0.j           -32.+651.374964j     -32.+324.9014524j
   -32.+215.72647697j   -32.+160.87486375j   -32.+127.75116108j
   -32.+105.48986269j   -32. +89.43400872j   -32. +77.254834j
   -32. +67.65831544j   -32. +59.86778918j   -32. +53.38877458j
   -32. +47.89138441j   -32. +43.14700523j   -32. +38.99211282j
   -32. +35.30655922j   -32. +32.j           -32. +29.00310941j
   -32. +26.26172131j   -32. +23.73281748j   -32. +21.38171641j
   -32. +19.18006188j   -32. +17.10435635j   -32. +15.13487283j
   -32. +13.254834j     -32. +11.44978308j   -32.  +9.70709388j
   -32.  +8.01558273j   -32.  +6.36519576j   -32.  +4.7467516j
   -32.  +3.15172491j   -32.  +1.57205919j   -32.  +0.j
   -32.  -1.57205919j   -32.  -3.15172491j   -32.  -4.7467516j
   -32.  -6.36519576j   -32.  -8.01558273j   -32.  -9.70709388j
   -32. -11.44978308j   -32. -13.254834j     -32. -15.13487283j
   -32. -17.10435635j   -32. -19.18006188j   -32. -21.38171641j
   -32. -23.73281748j   -32. -26.26172131j   -32. -29.00310941j
   -32. -32.j           -32. -35.30655922j   -32. -38.99211282j
   -32. -43.14700523j   -32. -47.89138441j   -32. -53.38877458j
   -32. -59.86778918j   -32. -67.65831544j   -32. -77.254834j
   -32. -89.43400872j   -32.-105.48986269j   -32.-127.75116108j
   -32.-160.87486375j   -32.-215.72647697j   -32.-324.9014524j
   -32.-651.374964j  ]



The following dependencies are required to build, run and test the package:

  • setuptools
  • pkgconfig
  • numpy
  • cffi
  • nose

An installation of the FFTW library is required. It should be discoverable with a call to pkg-config:

$ pkg-config --libs fftw3

Local or non-system installation locations are supported using PKG_CONFIG_PATH:

$ export PKG_CONFIG_PATH=$HOME/local/lib/pkgconfig
$ pkg-config --libs fftw3

Using pip

The recommended way to install the package is via pip:

$ pip install fftw-cffi


This method is suitable for environments where pip is not available, or for testing modifications to the package:

$ python install



The development team welcomes feedback, code and enhancement proposals to the package from the community. Please consider opening an issue or submitting patches for inclusion to the code base via pull-request. For code contributions, please provide appropriate test cases for each new features and verify that the complete test suite runs successfully.

Running the tests

If the bindings were modified, then one should first rebuild the CFFI module with:

$ python build_ext --inplace

Before running the test suite with a call to:

$ python nosetests


The fftw-cffi source code is released under the terms of the new BSD license. The copyright information can be checked out in the accompanying LICENSE file.

A separate installation of the FFTW library is required. The source code can be downloaded from the official homepage and installed following the instructions available in the corresponding README file. The FFTW library is licensed under the GPL version 2 or later.

Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Files for fftw-cffi, version 0.1
Filename, size File type Python version Upload date Hashes
Filename, size fftw-cffi-0.1.tar.gz (5.5 kB) File type Source Python version None Upload date Hashes View

Supported by

Pingdom Pingdom Monitoring Google Google Object Storage and Download Analytics Sentry Sentry Error logging AWS AWS Cloud computing DataDog DataDog Monitoring Fastly Fastly CDN DigiCert DigiCert EV certificate StatusPage StatusPage Status page