program example;
uses fftw;
const s=128;
var i,o:Pcomplex_single;
p:fftw_plan_single;
a:cardinal;
begin
fftw_getmem(i,s*sizeof(complex_single));
fftw_getmem(o,s*sizeof(complex_single));
p:=fftw_plan_dft_1d(128,i,o,fftw_forward,[fftw_estimate]);
for a:=0 to 127 do
begin
i[a].re:=(single(a)-64);
i[a].im:=0;
end;
writeln('input:');
for a:=0 to 127 do
writeln('(',i[a].re:8:4,',',i[a].im:8:4,')');
fftw_execute(p);
writeln('output:');
for a:=0 to 127 do
writeln('(',o[a].re:8:4,',',o[a].im:8:4,')');
fftw_destroy_plan(p);
fftw_freemem(i);
fftw_freemem(o);
end.
syntax highlighted by Code2HTML, v. 0.9.1