Graphics Programs Reference
In-Depth Information
a=[123;456;789]
matlab responds with
a=
1
2
3
4
5
6
7
8
9
3.2 Concatenating Matrices
Matrices can be made up of submatrices: Try this:
>>b=[a10*a;-a [1 0 0;0 1 0;0 0 1]]
b=
1
2
3
10
20
30
4
5
6
40
50
60
7
8
9
70
80
90
-1
-2
-3
1
0
0
-4
-5
-6
0
1
0
-7
-8
-9
0
0
1
The
repmat
function can be used to replicate a matrix:
>>a=[12;34]
a=
1 2
3 4
>> repmat(a,2,3)
ans =
1
2
1
2
1
2
3
4
3
4
3
4
1
2
1
2
1
2
3
4
3
4
3
4
3.3 Useful Matrix Generators
matlab provides four easy ways to generate certain simple matrices.
These are
zeros
a matrix filled with zeros
ones
a matrix filled with ones
rand
a matrix with uniformly distributed random elements
randn
a matrix with normally distributed random elements
eye
identity matrix
To tell matlab how big these matrices should be you give the functions
the number of rows and columns. For example:
