samer@0: % apowspec - Arrow to compute power spectra
samer@0: %
samer@0: % apowspec ::
samer@0: %    [[N]] ~'analysis window'
samer@0: % -> arrow( {[[N]]}, {[[dftbins(N)]]}, empty).
samer@0: % 
samer@0: % apowspec ::
samer@0: %    [[M]] ~'analysis window',
samer@0: %    N     ~'size for FFT'
samer@0: % -> arrow( {[[M]]}, {[[dftbins(N)]]}, empty).
samer@0: function [o,fx]=apowspec(window,N)
samer@0: 	W=spdiag(window);
samer@0: 	if nargin<2, N=length(window); end
samer@0: 	fx=(0:dftbins(N)-1)/N;
samer@0: 	o=arr(@ps);
samer@0: 	function y=ps(x)
samer@0: 		y=powspec(W*x,N);
samer@0: 	end
samer@0: end