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## -*- texinfo -*-
## @deftypefn {} {@var{retval} =} triangle_sw (@var{n}, @var{b})
## Triangular spectral window.
##
## Subfunction used for spectral density estimation.
## @seealso{spectral_xdf}
## @end deftypefn

function retval = triangle_sw (n, b)

  retval = zeros (n,1);
  retval(1) = 1 / b;

  l = (2:n)' - 1;
  l = 2 * pi * l / n;

  retval(2:n) = b * (sin (l / (2*b)) ./ sin (l / 2)).^2;

endfunction