import numpy h = [-8,-9,-3,-1,-6,7] f = [-3,-6,-1,8,-6,3,-1,-9,-9,3,-2,5,2,-2,-7,-1] g = [24,75,71,-34,3,22,-45,23,245,25,52,25,-67,-96,96,31,55,36,29,-43,-7] # https://stackoverflow.com/questions/14267555/find-the-smallest-power-of-2-greater-than-n-in-python def shift_bit_length(x): return 1<<(x-1).bit_length() def conv(a, b): p = len(a) q = len(b) n = p + q - 1 r = shift_bit_length(n) y = numpy.fft.ifft(numpy.fft.fft(a,r) * numpy.fft.fft(b,r),r) return numpy.trim_zeros(numpy.around(numpy.real(y),decimals=6)) def deconv(a, b): p = len(a) q = len(b) n = p - q + 1 r = shift_bit_length(max(p, q)) y = numpy.fft.ifft(numpy.fft.fft(a,r) / numpy.fft.fft(b,r), r) return numpy.trim_zeros(numpy.around(numpy.real(y),decimals=6)) # should return g print(conv(h,f)) # should return h print(deconv(g,f)) # should return f print(deconv(g,h))