1 ! Copyright (c) 2014 John Benediktsson
2 ! See http://factorcode.org/license.txt for BSD license.
4 USING: alien.c-types destructors fftw.ffi kernel math
5 math.vectors sequences sequences.private specialized-arrays ;
6 SPECIALIZED-ARRAY: double
7 SPECIALIZED-ARRAY: fftw_complex
13 : <fftw-array> ( length -- array )
14 [ fftw_complex heap-size * fftw_malloc &fftw_free ] keep
15 fftw_complex-array boa ;
17 : >fftw-array ( seq -- array )
18 [ length <fftw-array> ] keep over '[
19 [ >rect 0 1 ] [ _ nth ] bi*
20 [ set-nth-unsafe ] curry bi-curry@ bi*
23 : fftw-array> ( array -- seq )
24 [ first2 rect> ] { } map-as ;
26 :: (fft1d) ( seq sign -- seq' )
32 sign FFTW_ESTIMATE fftw_plan_dft_1d
33 [ fftw_execute ] [ fftw_destroy_plan ] bi
39 : fft1d ( seq -- seq' ) FFTW_FORWARD (fft1d) ;
41 : ifft1d ( seq -- seq' )
42 [ FFTW_BACKWARD (fft1d) ] [ length v/n ] bi ;
44 : correlate1d ( x y -- z )
45 [ fft1d ] [ reverse fft1d ] bi* v* ifft1d ;