Function: pheaviside

PHEAVISIDE  Periodic Heaviside function
  Usage: h=pheaviside(L);

  PHEAVISIDE(L) returns a periodic Heaviside function. The periodic
  Heaviside function takes on the value 1 for indices corresponding to
  positive frequencies, 0 corresponding to negative frequencies and the
  value .5 for the zero and Nyquist frequencies.

  To get a function that weights the negative frequencies by 1 and the
  positive by 0, use involute(PHEAVISIDE(L))

  As an example, the PHEAVISIDE function can be use to calculate the
  Hilbert transform for a column vector f*:

    h=2*ifft(fft(f).*pheaviside(length(f)));

Url: http://ltfat.github.io/doc/fourier/pheaviside.html

See also: middlepad, involute, fftindex.

Package: ltfat