% apowspec1 - Arrow to compute power spectra (automatic sizing version)
%
% apowspec1 ::
%    (N:natural -> [[N]]) ~'analysis window function'
% -> arrow( {[[N]]}, {[[dftbins(N)]]}, empty).
 
function o=apowspec1(windowfn)
	o=arrf(@mk,1,1);
	function f=mk(sizes)
		N=sizes{1}(1);	
		W=spdiag(windowfn(N));
		f=@(x)powspec(W*x,N);
	end
end
