MatlabNotes

Contents1 MATLAB 22 Starting Up 23 Matlab as a Calculator 34 Numbers & Formats 35 Variables 35.1 Variable Names . . . . . . . . . . 36 Suppressing output 47 Built–In Functions 47.1 Trigonometric Functions . . . . . 47.2 Other Elementary Functions . . . 48 Vectors 58.1 The Colon Notation . . . . . . . 58.2 Extracting Parts of Vectors . . . 68.3 Column Vectors . . . . . . . . . . 68.4 Transposing . . . . . . . . . . . . 69 Keeping a record 710 Script Files 711 Keyboard Accelerators 812 Arithmetic with Vectors 812.1 Inner Product (*) . . . . . . . . . 812.2 Elementwise Product (.*) . . . . 912.3 Elementwise Division (./) . . . . 1012.4 Elementwise Powers (.^) . . . . . 1113 Plotting Functions 1213.1 Plotting—Titles & Labels . . . . 1213.2 Grids . . . . . . . . . . . . . . . . 1213.3 Line Styles & Colours . . . . . . 1213.4 Multi–plots . . . . . . . . . . . . 1313.5 Hold . . . . . . . . . . . . . . . . 1313.6 Hard Copy . . . . . . . . . . . . 1313.7 Subplot . . . . . . . . . . . . . . 1413.8 Zooming . . . . . . . . . . . . . . 1413.9 Figure Properties . . . . . . . . . 1413.10Formatted text on Plots . . . . . 1513.11Controlling Axes . . . . . . . . . 1615 Two–Dimensional Arrays 1715.1 Size of a matrix . . . . . . . . . . 1815.2 Transpose of a matrix . . . . . . 1815.3 Special Matrices . . . . . . . . . 1815.4 The Identity Matrix . . . . . . . 1915.5 Diagonal Matrices . . . . . . . . 1915.6 Building Matrices . . . . . . . . . 2015.7 Tabulating Functions . . . . . . . 2015.8 Extracting Parts of Matrices . . 2015.9 Elementwise Products (.*) . . . 2115.10Matrix–vector products . . . . . 2115.11Matrix–Matrix Products . . . . . 2215.12Sparse Matrices . . . . . . . . . . 2316 Systems of Linear Equations 2316.1 Overdetermined systems . . . . . 2417 Characters, Strings and Text 2618 Loops 2719 Timing 2820 Logicals 2820.1 While Loops . . . . . . . . . . . . 2920.2 if...then...else...end . . . . 3021 Further Built–in Functions 3121.1 Rounding Numbers . . . . . . . . 3121.2 The sum Function . . . . . . . . . 3121.3 max & min . . . . . . . . . . . . . 3221.4 Random Numbers . . . . . . . . 3221.5 find for vectors . . . . . . . . . . 3221.6 find for matrices . . . . . . . . . 3222 Function m–files 3323 Plotting Surfaces 3624 Reading/Writing Data Files 3824.1 Formatted Files . . . . . . . . . . 3924.2 Unformatted Files . . . . . . . . 3925 Graphic User Interfaces 4026 Command Summary 4114 Elementwise Examples 171