HP 48GII User Manual

2-26 RPL Programming Examples
NAMES is demonstrated in the program VFY.
VFY (Verify Program Argument)
VFY verifies that an argument on the stack is either a name or a list that contains exactly two names.
Level 1 " Level 1
'name'
"
'name'
{ valid list }
"
{ valid list }
{ invalid list }
"
{ invalid list } (and error message in status area)
invalid object
"
invalid object (and error message in status area)
Techniques used in VFY
! Utility programs. VFY by itself has little use. However, it can be used with minor modifications by other
programs to verify that specific object types are valid arguments.
! CASE…END (case structure). VFY uses a case structure to determine if the argument is a list or a name.
! Structured programming. If the argument is a list, VFY calls NAMES to verify that the list contains exactly
two names.
! Local variable structure. VFY stores its argument in a local variable so that it can be passed to NAMES if
necessary.
! Logical function. VFY uses NOT to display an error message.
Required Programs
NAMES
! NAMES (Check List for Exactly Two Names) verifies that a list argument contains exactly two names.
VFY program listing
Program: Comments:
"!
452!
Copies the original argument to leave on the
stack.
4:B>!
Removes any tags from the argument for
subsequent testing.
#!$jmo!
Stores the argument in local variable argm.
"!
OBD<!
$jmo!:P2<!Qd!DBM<!
:;<=!
$jmo!=BM<D!
<=4!
Begins the defining procedure.
Begins the case structure.
Tests if the argument is a list.
If so, puts the argument back on the stack and
calls NAMES to verify that the list is valid,
then leaves the CASE structure.

HP 48GII Specifications

General

Battery type	CR2032
Type	Scientific
Form factor	Pocket

Weight and Dimensions

Weight	220 g
Dimensions (WxDxH)	184 x 87 x 23.5 mm

Summary

RPL Programming

Understanding Programs

Programs as objects, delimiters, and basic structure.

Entering and Executing Programs

Details on how to create, store, and run programs.

Using Conditional Structures

Covers IF, CASE, IFT, IFTE structures for program decision-making.

Input and Output Commands

Details commands like PROMPT, INPUT, INFORM, CHOOSE for user interaction.

RPL Programming Examples

Fibonacci Numbers

Demonstrates recursive and loop-based Fibonacci calculations.

Minimum and Maximum Array Elements

Details finding min/max elements using MNX and MNX2.

Applying a Program to an Array

Explains the APLY command for transforming array elements.

Full Command and Function Reference

How to Access Commands and Functions

Explains key presses and menu paths to access commands.

ABS (Absolute Value)

Details the absolute value function and its array behavior.

ACOS (Arc Cosine)

Explains the inverse cosine function, domain, and range.

Computer Algebra Commands

CAS Operations

Overview of CAS operations and their categorization by menu.

Algebra commands

Lists and describes commands for algebraic manipulation.

Calculus Commands

Covers derivation, integration, and limit commands.

Equation Reference

Columns and Beams (1)

Provides equations for structural mechanics.

Electricity (2)

Lists equations related to electrical circuits and laws.

Fluids (3)

Covers equations for fluid mechanics.

The Development Library

Introduction

Explains the purpose and usage of the development library.

Tools for Development

Details APEEK, PEEK, POKE, POKEARM commands.

MASD Compiler

Discusses syntax, modes, and directives for MASD.

Error and Status Messages

Messages Listed Alphabetically

Alphabetical list of error messages.

Messages Listed Numerically

Numerical list of error messages by hex code.

System Flags

System Flags (continued)

Description of various system flags.

System Flags (continued)

Continuation of system flags description.

Reserved Variables

Contents of the Reserved Variables

Explanation of key reserved variables.

PPAR

Details plotting parameters.

Technical Reference

Object Sizes

Lists object sizes in bytes.

Symbolic Integration Patterns

Provides a table of symbolic integration patterns.

Parallel Processing With Lists

General rules for parallel processing

Explains conditions for parallel list processing.

Group 4: ADD and +

Describes how ADD and + handle parallel list operations.

Keyboard Shortcuts

Press and Hold key combinations

Lists functions performed by key combinations.

Shifted softkeys

Explains shift key effects on menu labels.

The Menu-Number Table

-- menus 0-117 are semi-compatible with 48G menus --

Menu numbers and paths for built-in menus.

-- New Library 222 commands --

Details commands available in Library 222.