**OUTLINE**

1.1 MATLAB Interactive Sessions

1.2 Menus and the Toolbar

1.3 Computing with MATLAB

1.4 Script Files and the EditorlDebugger

1.5 The MATLAB Help System

1.6 Programming in MATLAB

1.7 Problem-Solving Methodologies

1.8 Summary

Problems

This is the most important in the book. By the time you have finished , you will be able to use MATLAB to solve many kinds of engineering problems. Section 1.1 provides a “quick-start” introduction to MATLAB as an interactive calculator. Section 1.2 covers the main menus and tool bar; Section 1.3 gives an overview of MATLAB, and directs the reader to the appropriate where more detailed information is available. Section 1.4 discusses how to create, edit, and save MATLAB programs. Section 1.5 introduces the extensive MATLAB Help System. Section 1.6 treats the use of conditional ‘statements and loops. Section 1.7 discusses methodologies for approaching engineering problems, with particular emphasis on a methodology to use with computer software such as MATLAB. A number of practice problems are given at the end .

**How to Use This Book**

The book’s organization is flexible enough to accommodate a variety of users. However, it is important to cover at least the first four , in that order covers arrays, which are the basic building blocks in MATLAB. covers file usage, functions built into MATLAB, and user-defined functions covers programming using relational and logical operators, conditional statements, and loops.

Use Section 1.3 to determine those MATLAB features for which you want more detailed information. This section will guide you to the appropriate through 10 are independent that can be covered in any order, or can be omitted. They contain in-depth discussions of how to use MATLAB to solve several common types of engineering problems covers two and three-dimensional plots in more detail, and shows how to use plots to build mathematical models from data. treats the solution of linear algebraic equations, including cases having nonunique solutions covers probability, statistics, and interpolation applications introduces numerical methods for calculus and ordinary differential equations covers Simulink, which is a graphical user interface for solving differential equation models covers symbolic processing in MATLAB, with applications to algebra, calculus, differential equations, linear algebra, and transforms.

**Reference and Learning Aids**

The book has been designed as a reference as well as a learning tool. The special features useful for these purposes are as follows.

- Throughout each margin notes identify where new terms are introduced.
- Throughout each short Test Your Understanding exercises appear. Where appropriate, answers immediately follow the exercise so you can measure your mastery of the material.
- Homework exercises conclude each. These usually require more effort than the Test Your Understanding exercises.
- Each contains tables summarizing the MATLAB commands introduced in that .
- At the end of each is:

A summary guide to the commands covered in that,

A summary of what you should be able to do after completing that, and

A Iist of key terms you should know. - Appendix A contains tables of MATLAB commands, grouped by category, with the appropriate page references.
- Two indexes are included. The first is an index of MATLAB commands and symbols; the second is an index of topics.

**Software Updates and Accuracy**

Software publishers can release software updates faster than book publishers can release new editions. This text documents the pre-release version of MATLAB 7 as of the spring of 2004. There will be additional updates, numbered 7.1, 7.2, and so forth, that will change some of the program’s features. The best way to protect yourself against obsolete information is to check the “What’s New?” file provided with the program, and to learn how to use the extensive MATLAB Help System, which is covered in Section 1.5.

**MATLAB and Related Software**

MATLAB is both a computer programming language and a software environment for using that language effectively. It is maintained and sold by The Math Works, Inc, of Natick, Massachusetts, and is available for MS Windows and other computer systems. The MATLAB interactive environment allows you to manage variables, import and export data, perform ‘calculations, generate plots, and develop and manage files for use with MATLAB. The language was originally developed in the 1970s for applications involving matrices, linear algebra, and numerical analysis (the name MATLAB stands for “Matrix Laboratory”). Thus the language’s numerical routines have been well-tested and improved through many years of use, and its capabilities have been greatly expanded.

MATLAB has a number of add-on software modules, called toolboxes, that perform more specialized computations. They can be purchased separately, but all run under the core MATLAB program. Toolboxes deal with applications such as image and signal processing, financial analysis, control systems design, and

fuzzy logic. An up-to-date list can’be found at The Math Works website, which is discussed later in this. This text uses material from the MATLAB program, from two of the toolboxes (the Control Systems toolbox, in , and the Symbolic Math toolbox ), and from Simulink . All of the examples and problems in the first seven can be done with the core MATLAB program.

On MS Windows systems MATLAB 7 requires Windows XP or Windows NT to run. The Student Edition of MATLAB contains the core MATLAB program, some commands from two toolboxes (the Signal Processing toolbox and the Symbolic Math toolbox), and the Simulink program. The Simulink program is based on MATLAB, and requires MATLAB to run.

This book does not explain how to install MATLAB. If you purchased it for your own computer, the installation is easily done with the instructions that come with the software. If you will be using MATLAB in a computer lab, it will have been installed for you.

In the next section we introduce MATLAB by means of some simple sessions to illustrate its interactive nature, basic syntax, and features.