Returning from a Function (GNU Octave (version 7.1.90))

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### 11.3 Returning from a Function

The body of a user-defined function can contain a `return` statement. This statement returns control to the rest of the Octave program. It looks like this:

    return

Unlike the `return` statement in C, Octave’s `return` statement cannot be used to return a value from a function. Instead, you must assign values to the list of return variables that are part of the `function` statement. The `return` statement simply makes it easier to exit a function from a deeply nested loop or conditional statement.

Here is an example of a function that checks to see if any elements of a vector are nonzero.

    function retval = any_nonzero (v)
      retval = 0;
      for i = 1:length (v)
        if (v (i) != 0)
          retval = 1;
          return;
        endif
      endfor
      printf ("no nonzero elements found\n");
    endfunction

Note that this function could not have been written using the `break` statement to exit the loop once a nonzero value is found without adding extra logic to avoid printing the message if the vector does contain a nonzero element.

: return ¶

  When Octave encounters the keyword `return` inside a function or script, it returns control to the caller immediately. At the top level, the return statement is ignored. A `return` statement is assumed at the end of every function definition.