argn

Description

This function is used inside a function definition. It gives the number of actual inputs arguments (rhs) and output arguments (lhs) passed to the function when the function is called. It is usually used in function definitions to deal with optional arguments.

Note that lhs is always greater than or equal to 1. That is to say, even if a function is called without having mentioned an output argument, lhs will be equal to 1.

Examples

function concat=myOwnFunction(name, optional)
  [lhs,rhs]=argn(0);
  disp(lhs);
  if rhs <= 1 then
       optional="my Optional value";
  end
  if rhs == 0 then
       error("Expect at least one argument");
  end
  concat=name+" "+optional;
endfunction

See also

• function — opens a function definition
• varargin — variable number of arguments in an input argument list