samer@4: % scanl - scanl for cell arrays
samer@4: %
samer@4: % scanl :: 
samer@4: %    (S,X->S)   ~'scannning function',
samer@4: %    S          ~'initial value',
samer@4: %    {[N]->X}   ~'data to scan, sequence of length L'
samer@4: % -> {[N]->S}.
samer@4: 
samer@4: function Y=scanl(f,y,X,varargin)
samer@4: 	Y=cell(size(X));
samer@4: 	if nargin>3
samer@4: 		opts=prefs('draw',0,varargin{:});
samer@4: 		for i=1:size(X,2)
samer@4: 			y1=f(y,X{i});
samer@4: 			Y{i}=y1;
samer@4: 			if opts.draw, opts.plotfn(i,y,X{i},y1);  end
samer@4: 			optpause(opts);
samer@4: 			y=y1;
samer@4: 		end
samer@4: 	else
samer@4: 		for i=1:size(X,2), y=f(y,X{i}); Y{i}=y; end
samer@4: 	end
samer@4: 		
samer@4: