func BenchmarkFFTW(b *testing.B) {
in := fftw.Alloc1d(N)
out := fftw.Alloc1d(N)
plan := fftw.PlanDft1d(in, out, fftw.Forward, fftw.Estimate)
for i := 0; i < b.N; i++ {
plan.Execute()
}
}
func FFTWSpec(c gospec.Context) {
c.Specify("Check agains fftw", func() {
N := 2 * 3 * 5 * 7 * 11
in := make([]complex128, N)
out_fft := make([]complex128, N)
out_fftw := make([]complex128, N)
for i := range in {
in[i] = complex(float64(i/1000-100), float64(i)/10)
}
fftw.PlanDft1d(in, out_fftw, fftw.Forward, fftw.Estimate).Execute()
fft.FFT(in, out_fft)
tolerance := 1e-5
for i := range out_fft {
c.Expect(real(out_fft[i]), IsWithin(tolerance), real(out_fftw[i]))
c.Expect(imag(out_fft[i]), IsWithin(tolerance), imag(out_fftw[i]))
}
})
}