>> Honestly, I don't find "forward" very informative. There isn't any real
>> convention on whether FFT of IFFT have any normalization.
>> To the best of my experience, either forward or inverse could be normalized
>> by 1/N, or each normalized by 1/sqrt(N), or neither
>> could be normalized. I
>> There may be another very concrete one (that's not yet in the NEP): allowing
>> other libraries that consume ndarrays to use overrides. An example is
>> numpy.fft: currently both mkl_fft and pyfftw monkeypatch NumPy, something we
>> don't like all that much (in particular for mkl_fft, because
