GNU Octave Manual Version 3 by John W. Eaton, David Bateman, Søren Hauberg Paperback (6"x9"), 568 pages ISBN 095461206X RRP £24.95 ($39.95) |
11.5 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.
- Keyword: 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. Areturn
statement is assumed at the end of every function definition.
ISBN 095461206X | GNU Octave Manual Version 3 | See the print edition |