Page 235 -

8

Matrices

8.1 Setting up Matrices
DEFINITION A matrix is a collection of numbers arranged in a two-dimen-
sional (2-D) array structure. Each element of the matrix, call it M , occupies
i,j
th
th
the i row and j column.
 M 11 M 12 M 13 L M 1 n 
 M M M L M 
M =  21 22 23 2 n  (8.1)
 M M M O M 
 
 M m1 M m2 M m3 L M mn 

We say that M is an (m ⊗ n) matrix, which means that it has m rows and n
columns. If m = n, we call the matrix square. If m = 1, the matrix is a row vec-
tor; and if n = 1, the matrix is a column vector.

8.1.1 Creating Matrices in MATLAB
8.1.1.1 Entering the Elements
In this method, the different elements of the matrix are keyed in; for example:

M=[1 3 5 7 11; 13 17 19 23 29; 31 37 41 47 53]
gives

M =
1 3 5 7 11
13 17 19 23 29
31 37 41 47 53

0-8493-????-?/00/$0.00+$.50
© 2000 by CRC Press LLC
© 2001 by CRC Press LLC