HP 15c Collector's Edition User Manual

110 Section 10: The Index Register and Loop Control
For example, the number 0.05002 in a storage register represents:
nnnnn x x x y y
0.0 5 0 0 2
Start count at zero. Count by twos.
Count up to 50.
I and e Operation. Each time a program encounters I or e
it increments or decrements nnnnn (the integer portion of the loop
control number), thereby keeping count of the loop iterations. It
compares nnnnn to xxx, the prescribed test value, and exits the loop by
skipping the next line if the loop counter (nnnnn) is either greater than
(I) or less than or equal to (e) the test value (xxx). The amount
that nnnnn is incremented or decremented is specified by yy.
With these functions (as opposed to the other conditional tests), the rule
is “Skip if True”.
False (nnnnn ≤ xxx) True (nnnnn > xxx)
instruction
´ I V
loop
t . 1
instruction
exit loop
For I: given nnnnn.xxxyy, increment nnnnn to nnnnn + yy,
compare it to xxx, and skip the next program line if the new value
satisfies nnnnn > xxx. This allows you to exit a loop at this point when
nnnnn becomes greater than xxx.

HP 15c Collector's Edition Specifications

General

Model	HP 15c Collector's Edition
Category	Calculator
Type	Scientific
Power Source	Battery
Manufacturer	HP
Display	LCD
Functions	complex numbers, matrix operations

Summary

Introduction

This Handbook

Outlines the structure of the manual, detailing its parts and how to use it for learning.

The HP Community

Discusses user groups and websites for HP calculator enthusiasts and information sharing.

Part I: HP 15c Fundamentals

Section 1: Getting Started

Covers basic operations like powering on, keyboard layout, and primary/alternate functions.

Section 2: Numeric Functions

Explains essential numeric operations including logs, trig, powers, and conversions.

Section 3: The Automatic Memory Stack, LAST X, and Data Storage

Details the RPN stack, LAST X register, and data storage operations.

Part II: HP 15c Programming

Section 6: Programming Basics

Introduces core programming concepts: creating, loading, running programs, and memory.

Section 8: Program Branching and Controls

Covers controlling program flow using branching, loops, and conditional tests.

Part III: HP 15c Advanced Functions

Section 11: Calculating With Complex Numbers

Covers entering, manipulating, and performing calculations with complex numbers.

Section 12: Calculating With Matrices

Explains matrix operations, including dimensioning, element access, and calculations.

Section 13: Finding the Roots of an Equation

Details using the SOLVE function for numerical root finding and equation solving.

Section 14: Numerical Integration

Explains how to perform numerical integration using the ∫f(x)dx key and subroutines.

Appendix A: Error Conditions

Error 8: No Root

Explains the error when the SOLVE function cannot find a root.

Error 0: Improper Mathematics Operation

Lists and explains errors related to mathematical operations and illegal arguments.

Appendix D: A Detailed Look at SOLVE

How SOLVE Works

Explains the numerical technique and logic behind the SOLVE algorithm.

Finding Several Roots

Discusses methods for finding multiple roots of an equation using the SOLVE function.