annotate general/funutils/@function_handle/gt.m @ 61:eff6bddf82e3 tip

Finally implemented perceptual brightness thing.

% gt - select outputs from function 
%
% gt :: (A{:}=>B{1:N}), I:[M]->[N]] -> (A{:}=>B{I}).
%
% f>[i,j,k...] is a function which takes the same arguments as f
% but returns the ith,jth,kth etc return values from f as the 1st, 2nd, 3rd etc
% return values.
% eg feval(@eig>2,X) returns the eigenvectors of X.

function g=gt(f,I,nin)
	if nargin<3, nin=nargin(f); end
	nout=length(I); MI=max(I);
	fns = { @q11, @q1n; @qn1, @qnn };
	g=fns{acount(nin,1),acount(nout,1)};

	function y=q11(x), [rets{1:MI}]=f(x); y=rets{I}; end
	function y=qn1(varargin), [rets{1:MI}]=f(varargin{:}); y=rets{I}; end
	function varargout=q1n(x), [rets{1:MI}]=f(x); varargout=rets(I); end
	function varargout=qnn(varargin), [rets{1:MI}]=f(varargin{:}); varargout=rets(I); end
end