With variables, you can store strings or numbers. Functions allow you to manipulate these strings or numbers. Functions work like mathematical functions: They take some number of arguments in, and return one argument, usually a number or a string for our purposes. There are a lot of functions available in LON-CAPA. You can see a complete list in the Script section and LON-CAPA function section .
For now, let's just look at some simple examples.
$a = -3.0;
$b = &sin($a);
$c = &pow(3.0, &abs($a));
In the Script block, function names start with &. Some example function calls are shown above. You can see that functions can take either variables, numbers, or the results of other function calls as parameters. The &sin function returns the sine of an angle expressed in radians. &pow raises the first parameter to the power of the second parameter. &abs returns the absolute value of the argument.