In the context I used it, FFT wasn’t really of fundamental importance. Using FFT (and in particular FFTW) gave a performance improvement (execution speed), but

In the context I used it, FFT wasn’t really of fundamental importance. Using FFT (and in particular FFTW) gave a performance improvement (execution speed), but no real advantage in terms of accuracy over an alternative naive method... So... yes I guess I’ve just not seen anywhere in my work where this stuff has proved useful...