Hermitian signal
  * **n** (*int**, **optional*) -- Output signal length. This
    determines the length of the real output. If given, the input
    will either be zero-padded or trimmed to this length before
    computing the Hermitian FFT. Defaults to even output:
    "n=2*(input.size(dim) - 1)".

  * **dim** (*int**, **optional*) -- The dimension along which to
    take the one dimensional Hermitian FFT.

  * **norm** (*str**, **optional*) --

    Normalization mode. For the forward transform ("hfft()"),
    these correspond to:

    * ""forward"" - normalize by "1/n"

    * ""backward"" - no normalization

    * ""ortho"" - normalize by "1/sqrt(n)" (making the Hermitian
      FFT orthonormal)

    Calling the backward transform ("ihfft()") with the same
    normalization mode will apply an overall normalization of
    "1/n" between the two transforms. This is required to make
    "ihfft()" the exact inverse.
