A Beginner's Guide to Matlab


Introduction

Matlab is a power computational and visualization software, which is widely used in the physics community. Matlab like Linux is a case dependent langauge (e.g. exp(x) is equivalent to the exponential function at a point x, whereas typing EXP(x) will produce an error). Unlike Fortran, Matlab automatically creates variables when they are needed because of this fact it is very important that variable names do not include function names.

Tricks

  • ending a line with ... allows you to split a command between multiple lines

  • ending a line with ; prevents the computed value from being printed on the screen

  • multiple commands can occupy one line if they are seperated by a , [comma]

  • tab will autocomplete a command or file name

  • pressing the up arrow will retrieve previous commands

    Read Data From a File

    1. Drag file into Matlab window- This automatically intiates the uiopen command, which opens the user interface

    2. Enter data = dlmread('apple.csv, range)
    3. range = [1 1 2633 4]
    4. load('apple.csv',',')

    NOTE: .csv is a common suffix for a file of comma seperated variables

    Commands

  • whos-lists all variables

  • clear-clears all variables [clear a- clears variable named a]

  • pwd- prints where you are

  • ls- lists files in a directory (can use wildcards *.m)

  • cd- changes directory (cd .. up one, cd ~ home)

    Miscellaneous

  • pi and i are predefined variable names