An external Matlab/Octave file is called an *M files*.
First you have to save the M file of your interest in order to use it.
Then run Matlab/Octave and at the screen with prompt ```>`'' type

> cd [the directory where M files are saved]If you are using Octave, save M files under ``

`C:\Program Files\GNU Octave\`

'', simply type
> cdor ``

`cd /`

''; then check if the current place is ```/`

''
by typing ```pwd`

''.
To make sure whether the M file is under this directory,
we can use
> lsIf you see it, say ``

Here are a few M files we might want to use throughout this material:

idemo.m |
idemo('[script file]')
executes a Matlab/Octave script line by line.
In Matlab, you can call it by
> idemo(uigetfile('*.m','Load M file'))In Octave you have to set default_eval_print_flag = 1to display the output properly. |

rref.m |
R = rref (A, tol)
returns the reduced row echelon form of A. |

arrow.m |
arrow([x0,y0],[x1,y1])
drows an arrow from to
in xy-coordinate. |

pmatrix.m |
pmatrix(n)
generates an n-by-n probability transition matrix consisting of random
entries. |

You can find many more M files and custom scripts, and extensions for GNU Octave at GNU Octave Repository.

Department of Mathematics