Initial release of some heavily inlined fft routines. Source written in c. These routines can handle at most 4096 complex points or 8192 real points. Green - This is archived version of a routine that performs C FFT by John Green. Only works for powers of two.
Source codes are available.
Single precision and double precision are equally supported. We believe that FFTW, which is free software, should become the FFT library of choice for most applications. Our benchmarks, performed on on a variety of platforms, show that FFTW's performance is typically superior to that of other publicly available FFT software. It's also reasonably fast on other machines. The benchmark incorporates a large number of publicly-available FFT implementations, both in C and in Fortran, and measures their performance and accuracy over a wide range of transform sizes.