|软件描述：||FFTW is a C subroutine library for computing the discrete Fourier transform (DFT) in one or more dimensions, of arbitrary input size, and of both real and complex data (as well as of even/odd data, i.e. the discrete cosine/sine transforms or DCT/DST). We believe that FFTW, which is free software, should become the FFT library of choice for most applications.|
Here is a list of some of FFTW's more interesting features:
• Speed. (Supports SSE/SSE2/Altivec, since version 3.0. Version 3.3.1 supports AVX and ARM Neon.)
• Both one-dimensional and multi-dimensional transforms.
• Arbitrary-size transforms. (Sizes with small prime factors are best, but FFTW uses O(N log N) algorithms even for prime sizes.)
• Fast transforms of purely real input or output data.
• Efficient handling of multiple, strided transforms. (This lets you do things like transform multiple arrays at once, transform one dimension of a multi-dimensional array, or transform one field of a multi-component array.)
• Parallel transforms: parallelized code for platforms with SMP machines with some flavor of threads (e.g. POSIX) or OpenMP. An MPI version for distributed-memory transforms is also available in FFTW 3.3.
• Portable to any platform with a C compiler.
• Documentation in HTML and other formats.
• Both C and Fortran interfaces.
• Free software, released under the GNU General Public License (GPL, see FFTW license). (Non-free licenses may also be purchased from MIT, for users who do not want their programs protected by the GPL. Contact us for details.) (See also the FAQ.)
If you are still using FFTW 2.x, please note that FFTW 2.x was last updated in 1999 and it is obsolete. Please upgrade to FFTW 3.x. The API of FFTW 3.x is incompatible with that of FFTW 2.x, for reasons of performance and generality (see the FAQ or the manual).
（Reference to http://www.fftw.org/）