program that calls itself

How do I write a function file that calls itself without getting stuck in an infinite loop? I just want the program to call itself once.

Answer 1

[Andrew Newell]

See Recursion - a conceptual example.

Answer 2

[Walter Roberson]

Very simple example:

function x = foo(a,b)
  if ~exist('b','var'); x = foo(a,0); return; end
  x = a + b;
end