samer@0: % alpc - LPC arrow
samer@0: %
samer@0: % alpc ::
samer@0: %    N:natural   ~'size of waveform blocks to expect',
samer@0: %    M:natural   ~'order of LPC to do'
samer@0: %    options {
samer@0: %       specfn :: ([[N,T]]->[[dftbins(N),T]])/ @powspec ~'function to compute spectra';
samer@0: %       window :: (N:natural->[[N]])         / @hanning ~'function to compute window'
samer@0: %    }
samer@0: % -> arrow({[[N,1]]},{[[M,1]]},empty).
samer@0: 
samer@0: function o=alpc(N,M,varargin)
samer@37: 	opts=options('window',@hanning,'nargout',1,varargin{:});
samer@0: 	w=spdiag(opts.window(N));
samer@0: 	if opts.nargout<=1
samer@0: 		o=arr(@fn);
samer@0: 	else
samer@0: 		o=arr(@fn2);
samer@0: 	end
samer@0: 
samer@0: 	function y=fn(x)
samer@0: 		y=lpc(w*x,M);
samer@0: 	end
samer@0: 
samer@0: 	function [y,v]=fn2(x)
samer@0: 		[y,v]=lpc(w*x,M);
samer@0: 	end
samer@0: end