Get a function to return a comma-separated variable list?

Dear All,

for compactness, I was looking for a way to get a function, called with no output arguments, to return all the outputs (not just the first), analogous to e.g. C{:} for a cell array. The aim is to streamline certain codes, where the function will return a variable-length list of outputs to be used as a list of inputs for another function. As an example:

function test_output_vars()

figure(1), clf
list=plot_list1;
plot(list{:}) % Two-liner with intermediate cell array 
hold on
plot(plot_list2) % Desired one-liner, but only captures first output variable

[x,y,lt]=plot_list2(); % Works of course, but not what I'm aiming at

end

function list=plot_list1()
list={1:10,1:2:19,'o-'};
end

function varargout=plot_list2()
varargout={1:10,1:2:19,'o-'};
nargout % indeed, will =1 when called with no outputs... 
end

Is there any "simple" way to achieve this (besides some tricks with a custom class and overloading numArgumentsFromSubscript)?

Regards, MT

Answer 1

[Walter Roberson]

No, this is not possible in MATLAB. Comma list expansion is syntactic, requiring a literal {} or expression followed by dot followed by field name.

[Walter Roberson]

plot(plot_list1().varargout)

function varargout = plot_list1()
list={1:10,1:2:19,'o-'};
if nargout > 0
  varargout = list;
 else
   varargout = {struct('varargout', list)} ;
 end 
end

[Mark Thomson]

Dear Walter,

many thanks for the guidance. Okay, returning a structure array is at least a working option.

Regards, MT