Matlab is a software package that makes it easier for you to enter matrices and vectors, and manipulate them. The interface follows a language that is designed to look a lot like the notation use in linear algebra. In the following tutorial, we will discuss some of the basics of working with vectors.
To start matlab, open up a unix shell and type the command to start the software: matlab. This will start up the software, and it will wait for you to enter your commands. In the text that follows, any line that starts with two greater than signs (>>) is used to denote the matlab command line. This is where you enter your commands.
Almost all of Matlabs basic commands revolve around the use
of vectors. To simplify the creation of vectors, you can
define a vector by specifying the first entry, an increment,
and the last entry. Matlab will automatically figure out
how many entries you need and their values.
For example, to create a vector whose entries are 0, 2, 4,
6, and 8, you can type in the following line:
>> 0:2:8
ans =
0 2 4 6 8
Matlab also keeps track of the last result. In the previous
example, a variable "ans" is created. To look at the transpose
of the previous result, enter the following:
>> ans'
ans =
0
2
4
6
8
To be able to keep track of the vectors you create, you can give them
names. For example, a row vector v can be created:
>> v = [0:2:8]
v =
0 2 4 6 8
>> v
v =
0 2 4 6 8
>> v;
>> v'
ans =
0
2
4
6
8
Note that in the previous example, if you end the line with a
semi-colon, the result is not displayed. This will come in
handy later when you want to use Matlab to work with very
large systems of equations.
Matlab will allow you to look at specific parts of the vector. If you want to only look at the first three entries in a vector you can use the same notation you used to create the vector:
>> v(1:3)
ans =
0 2 4
>> v(1:2:4)
ans =
0 4
>> v(1:2:4)'
ans =
0
4
Once you master the notation you are free to perform other
operations:
>> v(1:3)-v(2:4)
ans =
-2 -2 -2
The
next tutorial covers the use of matrices.
This tutorial written by Kelly Black.