absolute_handle.m

function h = absolute_handle(s)
% ABSOLUTE_HANDLE  Get function handle to a file, not necessarily on path
%    H = ABSOLUTE_HANDLE(S) get handle to function or script in file S

    [p,n,e] = fileparts(s);
    o = cd();
    if ~isempty(p)
        fu = onCleanup(@() clean(o));
        cd(p);
    end
    f = [fullfile(cd(), n) e];
    if ~( exist(f, 'file') == 2 ...
           || (isempty(e) && exist([f '.m'], 'file') == 2) )
        error('Could not find file %s', s);
    end
    h = str2func(n);
    try
        nargin(h);
    catch ME
        if ~strcmp(ME.identifier, 'MATLAB:nargin:isScript')
            error(ME.message);
        end
    end
end
function clean(o)
    cd(o);
end