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

Keyword

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.