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General Purpose FFT (Fast Fourier/Cosine/Sine Transform) Package

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• Brief Description
• Dependencies
• Git
• CMake
• Functions
• License

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Brief description:

The General Purpose FFT (Fast Fourier/Cosine/Sine Transform) Package:

• ANSI C library
• was only double precision floating point 'double'

This is a fork of his FFT Package - currently with some changes for the 1D-FFT:

• added cmake support, to build libraries
• added support for single precision 'float'
• added include headers
• enhanced tests/samples
• use ctest

Origin of this package is https://www.kurims.kyoto-u.ac.jp/~ooura/fft.html

Dependencies:

On Debian/Ubuntu Linux following packages should be installed:

sudo apt-get install build-essential gcc cmake git

Git:

This archive's source can be downloaded with git:

git clone https://github.com/hayguen/OouraFFT.git

CMake:

There's now CMake support to build the many libraries from the source files.

There are a few CMake options to modify library size and optimization. You can explore all available options with cmake-gui or ccmake, the console version - after having installed (on Debian/Ubuntu Linux) one of

sudo apt-get install cmake-qt-gui
sudo apt-get install cmake-curses-gui

The options:

• ARCH to set the target architecture for the compiler
• OOURA_USE_FLOAT_PREC to compile the libraries for single precision 'float', default is 'double'
• OOURA_USE_FAST_MATH to (de)activate fast floating point math

Options can be passed to cmake at command line, e.g.

cmake -DARCH=core2 -DOOURA_USE_FLOAT_PREC=ON

My Linux distribution defaults to GCC. With installed CLANG and the bash shell, you can use it with

mkdir build
cd build
CC=/usr/bin/clang CXX=/usr/bin/clang++ cmake -DCMAKE_BUILD_TYPE=Release ../
cmake -DCMAKE_BUILD_TYPE=Release -DARCH=core2 -DOOURA_USE_FLOAT_PREC=ON ../
ccmake .                          # or: cmake-gui .
cmake --build .                   # or simply: make

Functions:

Routines in the Package:

• cdft: Complex Discrete Fourier Transform
• rdft: Real Discrete Fourier Transform
• ddct: Discrete Cosine Transform
• ddst: Discrete Sine Transform
• dfct: Cosine Transform of RDFT (Real Symmetric DFT)
• dfst: Sine Transform of RDFT (Real Anti-symmetric DFT)

For details on parameters, see the original readme.txt or the new header files include/ooura/.

The 2D and 3D-routines are as-is from Takuya OOURA. See his notes in readme2d.txt

License:

MIT License, see LICENSE

Copyright(c) 2021 Hayati Ayguen

Copyright(C) 1996-2001 Takuya OOURA