| What is a subroutine? | Parts of a program can also be formulated elsewhere as a subroutine (subprogram), where the control flow
• branches there if required (call) and
• returns to the place of the call after the subroutine has terminated (return).
We use subroutines to
• factor out common parts of an algorithm for reuse
• structure larger programs in »digestible units« (modules) |
| What are parameters? | Parameters are means to communicate with subroutines:
• In the header, formal parameters are defined, which
• act like local variables within the subroutine, but are
• initialized by an actual parameter (value of an expression) each time the subroutine is called |
| Method overloading | Method names can occur multiple times as long as the methods with the same name differ sufficiently by number or data types of the formal parameters:Naming different things (usually methods) with the same name is called overloading.In a method call, the ambiguity (»Which method is meant?«) is resolved based on number and types of the actual parameters. |
| Riddle | RIDDLE IMPLEMENT THESE CHANGES
Extend the circle program by adding another for-loop around the circle drawing loop,
which runs, e.g., ten times. Starting with a value of, e.g., 0.1, after each circle segment, slightly enlarge the radius. |
| Riddle | RIDDLE IMPLEMENT THE VERSION WITH TRACE |
