Using MATLAB Graphics

372 Pages·1997·9.29 MB·English

M
ATLAB
(cid:210)
The Language of Technical Computing
Computation
Visualization
Programming
Using MATLAB Graphics
Version 5.2
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Using MATLAB Graphics
(cid:211) COPYRIGHT 1984 - 1997 by The MathWorks, Inc. All Rights Reserved.
The software described in this document is furnished under a license agreement. The software may be used
or copied only under the terms of the license agreement. No part of this manual may be photocopied or repro-
duced in any form without prior written consent from The MathWorks, Inc.
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have only the rights specified in the license under which the commercial computer software or commercial
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sure are as set forth in Clause 52.227-19 (c)(2) of the FAR.
MATLAB, Simulink, Handle Graphics, and Real-Time Workshop are registered trademarks and Stateflow
and Target Language Compiler are trademarks of The MathWorks, Inc.
Other product or brand names are trademarks or registered trademarks of their respective holders.
Printing History: December 1996First printing New for 5.0
June 1997 Revised for 5.1 (Online version)
January 1998 Revised for 5.2 (Online version)
Preface
What Is MATLAB? . . . . . . . . . . . . . . . . . . ii
MATLAB Documentation . . . . . . . . . . . . . . .iii
How to Use the Documentation Set. . . . . . . . . . . . .iii
Typographical and Alphabetic Conventions . . . . . . . . .iv
Preface
What Is MATLAB?
MATLAB® is a high-performance language for technical computing. It
integrates computation, visualization, and programming in an easy-to-use
environment where problems and solutions are expressed in familiar
mathematical notation. Typical uses include:
•Math and computation
•Algorithm development
•Modeling, simulation, and prototyping
•Data analysis, exploration, and visualization
•Scientific and engineering graphics
•Application development, including graphical user interface building
MATLAB is an interactive system whose basic data element is an array that
does not require dimensioning. This allows you to solve many technical
computing problems, especially those with matrix and vector formulations, in
a fraction of the time it would take to write a program in a scalar
noninteractive language such as C or Fortran.
The name MATLAB stands for matrix laboratory. MATLAB was originally
written to provide easy access to matrix software developed by the LINPACK
and EISPACK projects, which together represent the state-of-the-art in
software for matrix computation.
MATLAB has evolved over a period of years with input from many users. In
university environments, it is the standard instructional tool for introductory
and advanced courses in mathematics, engineering, and science. In industry,
MATLAB is the tool of choice for high-productivity research, development, and
analysis.
MATLAB features a family of application-specific solutions called toolboxes.
Very important to most users of MATLAB, toolboxes allow you to learn and
apply specialized technology. Toolboxes are comprehensive collections of
MATLAB functions (M-files) that extend the MATLAB environment to solve
particular classes of problems. Areas in which toolboxes are available include
signal processing, control systems, neural networks, fuzzy logic, wavelets,
simulation, and many others.
ii
MATLAB Documentation
MATLAB Documentation
MATLAB comes with an extensive set of both online and printed documenta-
tion. The online MATLAB Function Reference is a compendium of all MATLAB
commands functions. You can access this documentation from the MATLAB
Help Desk. Users on all platforms can access the Help Desk with the MATLAB
doc command. MS-Windows and Macintosh users can also access the Help
Desk with the Help menu or the ? icon on the Command Window toolbar. From
the Help Desk main menu, choose “MATLAB Functions” to display the Func-
tion Reference.
The online resources are augmented with printed documentation consisting of
the following titles:
•Getting Started with MATLAB describes MATLAB fundamentals.
•Using MATLAB explains how to use MATLAB as both a programming lan-
guage and a command-line application.
•Using MATLAB Graphics describes how to use MATLAB’s graphics and
visualization tools.
•Building GUIs with MATLAB dicusses the construction of graphical user
interfaces and introduces the Guide GUI building tool.
•The MATLAB Application Programmer’s Interface Guide explains how to
write C or Fortran programs that interact with MATLAB.
•The MATLAB 5 New Features Guide provides information useful in making
the transition from MATLAB 4.x to MATLAB 5.
•The MATLAB 5 Late-Breaking News provides additional information about
new features that are not covered in the other guides. They also include lists
of problems fixed since the previous release and known documentation
errors.
How to Use the Documentation Set
If you need to install MATLAB, you should read the appropriate booklet. Once
you install MATLAB, you can decide which document you prefer to use to learn
the MATLAB commands.
If you are a new MATLAB user, you should start by reading Getting Started
with MATLAB. Using MATLAB provides an extensive description of the
MATLAB language.
iii
Preface
Using MATLAB Graphics describes how to use MATLAB for visualizing data
with both high-level functions and Handle Graphics. Information about con-
structing user interfaces is provided in Building GUIs with MATLAB.
iv
Typographical and Alphabetic Conventions
Typographical and Alphabetic Conventions
This manual uses certain typographical conventions.
Font Usage
Monospace Commands, function names, and screen displays;
for example, conv.
Monospace Italics Names of arguments that are meant to be
replaced and not typed literally; for instance:
cd directory.
Italics Book titles, mathematical notation, and the
introduction of new terms.
Boldface Initial Cap Names of keys, such as the Return key.
v
Preface
vi
Contents
Preface
What Is MATLAB? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii
MATLAB Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii
How to Use the Documentation Set . . . . . . . . . . . . . . . . . . . . . . . iii
Typographical and Alphabetic Conventions . . . . . . . . . . . . . . . v
Introduction
1
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
High-Level Graphics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Handle Graphics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Building Interactive GUIs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
How It All Fits Together . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Where to Begin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Building 2-D Graphs
2
Building a 2-D Graph . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Figure Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Multiple Axis Regions (subplot) . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Default Color Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
i
Elementary Plotting Functions . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
Creating a Plot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
Adding Plots to an Existing Graph (hold) . . . . . . . . . . . . . . . . . 2-10
Matrix Data Plots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10
Imaginary and Complex Data . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12
Basic Plot Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14
Colors, Line Styles, and Markers . . . . . . . . . . . . . . . . . . . . . . . 2-14
Axis Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-15
Axis Tick Marks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-16
Axes Aspect Ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-17
Graph Annotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-19
Labeling the Individual Axes . . . . . . . . . . . . . . . . . . . . . . . . . . 2-19
Building 3-D Graphs
3
Building a 3-D Graph . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
Elementary 3-D Plotting Functions . . . . . . . . . . . . . . . . . . . . . 3-3
Line Plots in 3-D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Representing a Matrix as a Surface . . . . . . . . . . . . . . . . . . . . . 3-5
Mesh and Surface Plots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
Visualizing Functions of Two Variables . . . . . . . . . . . . . . . . . . . 3-6
Parametric Surfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
Hidden Line Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-11
Coloring Mesh and Surface Plots . . . . . . . . . . . . . . . . . . . . . . 3-12
Colormaps and Indexed Colors . . . . . . . . . . . . . . . . . . . . . . . . . 3-12
Truecolor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17
Texture Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-19
Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-21
Light Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-21
Properties that Affect Lighting . . . . . . . . . . . . . . . . . . . . . . . . . 3-22
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