Local variable scope, The prg menu, Local variable scope ,21-5 – HP 50g Graphing Calculator User Manual

Page 652: The prg menu ,21-5

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Page 21-5

Local Variable Scope

Local variables are active only within a program or sub-program. Therefore,
their scope is limited to the program or sub-program where they’re defined. An
example of a local variable is the index in a FOR loop (described later in this
chapter), for example «

n x

«

1 n FOR j x NEXT n

LIST

» »

The PRG menu

In this section we present the contents of the PRG (programming) menu with the
calculator’s system flag 117 set to SOFT menus. With this flag setting sub-
menus and commands in the PRG menu will be shown as soft menu labels. This
facilitates entering the programming commands in the line editor when you are
putting together a program.

To access the PRG menu use the keystroke combination „°. Within the
PRG menu we identify the following sub-menus (press L to move to the next
collection of sub-menus in the PRG menu):

Here is a brief description of the contents of these sub-menus, and their sub-
menus:
STACK: Functions for manipulating elements of the RPN stack
MEM:

Functions related to memory manipulation

DIR:

Functions related to manipulating directories

ARITH:

Functions to manipulate indices stored in variables

BRCH:

Collection of sub-menus with program branching and loop functions

IF:

IF-THEN-ELSE-END construct for branching

CASE:

CASE-THEN-END construct for branching

All these rule may sound confusing for a new calculator user. They all can be
simplified to the following suggestion: Create directories and sub-directories
with meaningful names to organize your data, and make sure you have all the
global variables you need within the proper sub-directory
.

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