function varargout = colfun(fn, varargin)
%COLFUN apply function to each column of array returning array of answers
%
% results = colfun(fn, A)
%   Apply function fn to each column of A and return each answer
%   as a column of results. Note that answers must stack side by side.
% 
% [a, b, ...] = colfun(fn, A)
%   Apply function fn to each column of A. Output a is an array containing
%   all of the first outputs. Likewise b contains all of the second outputs.
% 
% ... = colfun(fn, A, B, ...)
%   Now fn takes multiple arguments, taking a column from each of the input
%   arrays A, B, ...
%
% See also: rowfun, rowmap, colmap

% Iain Murray, November 2007

varargout = cell(1, max(1, nargout));
[varargout{:}] = dimfun(fn, 1, varargin{:});