InputParser and function handle

Hi,

I want to use the InputParser Class to check the inputs of a function. Basically my function looks like this

function a = myfun(b,varargin)

p = inputParser;

addRequired(p,'b',@isnumeric);
addOptional(p,'fun',@mean,@(x) isa(x,'function_handle'));

parse(p,b,varargin);

a = p.Results.fun(p.Results.b);

If I call this function, say with

a = myfun(rand(10,1),'fun',@mean)

Matlab throws an error saying

Error using myfun (line 8)
Argument 'fun' failed validation @(x)isa(x,'function_handle').

What am I doing wrong and what is the best way to pass a function handle through the inputParser?

Regards, Anon

Answer 1

[Wolfgang]

You have to write:

parse(p,b,varargin{:});

In your case, the function handle is presented to the parser as part of a cell array (varargin) so it doesn't recognize it correctly.

[Bjorn Gustavsson]

(I just ran into the same problem as Anon.) That varargin is a cell-array I understand, but shouldn't varargin{:} be the list of its contens, and that list is what the parse function should see?