MATLAB – Matrix
A matrix is a two-dimensional array of numbers.
In MATLAB, you create a matrix by entering elements in each row as comma or space delimited numbers
and using semicolons to mark the end of each row.
For example, let us create a 4-by-5 matrix a
a = [ 1 2 3 4 5; 2 3 4 5 6; 3 4 5 6 7; 4 5 6 7 8]
MATLAB will execute the above statement and return the following result –
a =
1 2 3 4 5
2 3 4 5 6
3 4 5 6 7
4 5 6 7 8
Referencing the Elements of a Matrix
To reference an element in the mth row and nth column, of a matrix mx, we write –
mx(m, n);
For example, to refer to the element in the 2nd row and 5th column, of the matrix a, as created in the
last section, we type –
a = [ 1 2 3 4 5; 2 3 4 5 6; 3 4 5 6 7; 4 5 6 7 8];
a(2,5)
MATLAB will execute the above statement and return the following result –
ans = 6
To reference all the elements in the mth column we type A(:,m).
Let us create a column vector v, from the elements of the 4th row of the matrix a:
a = [ 1 2 3 4 5; 2 3 4 5 6; 3 4 5 6 7; 4 5 6 7 8];
v = a(:,4)
MATLAB will execute the above statement and return the following result –
