12-2-8

Creating a New Program

kLocal Variables

A local variable is a variable that can be created temporarily and used in a program. Use the Local command to create a local variable.

Syntax: Local￿<variable name> (￿ indicates a space.)

Example: Local abc

The above creates a local variable named “abc”.

Tip

Local variables are deleted automatically after execution of a program is complete.

Note that local variables are stored in their own special folder, so local variable names do not affect the names of other variables in ClassPad memory. Because of this, you do not need to worry if you assign a local variable a name that is already being used by another type of variable.

Variables that are specified as parameter variables within a program are automatically treated as local variables. Variables created with the Define command are also automatically treated as local variables.

Using Subroutines

Including the name of another program file inside of a program causes execution to jump to the specified program file. The program that execution jumps from is called the “main program”, while the program to which execution jumps is called a “subroutine”.

When program execution returns to the main program, it resumes from the point immediately after the command that jumped to the subroutine.

Tip

Note that any program can be a subroutine. The thing that makes any program a subroutine is being jumped to from another program.

Main Program

 

 

Subroutines

 

 

 

 

 

 

 

 

 

 

 

 

A

D

 

 

 

 

 

 

 

 

D ( )

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

C ( )

C

 

E

 

 

I

 

J

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

E ( )

 

I ( )

 

 

J (

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Level 1

 

Level 2

 

Level 3

 

Level 4

Subroutines can be used in a variety of ways to help make calculations easier. Let’s say you have a formula that needs to be calculated more than once in a program, or that needs to be calculated by a number of different programs. Simply store the formula as a separate program file (subroutine), and then you can jump to the program file that contains the formula whenever you need it.

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