Creating an identity matrix in Matlab

The eye() function in MATLAB generates an identity matrix of any specified size.

eye(n)

Here, n sets both the number of rows and columns in the matrix.

For example, typing eye(2) creates a 2-by-2 identity matrix:

>> eye(2)
ans =
1 0
0 1

Likewise, typing eye(3) produces a 3-by-3 identity matrix:

>> eye(3)
ans =
1 0 0
0 1 0
0 0 1

Note: In an identity matrix, only the main diagonal contains ones, while all other elements are zero.

The eye() function can also accept two parameters:

eye(x, y)

In this format, x specifies the number of rows and y the number of columns.

For instance, typing eye(3,5) creates a 3-by-5 matrix with ones along the main diagonal:

>> eye(3,5)
ans =
1 0 0 0 0
0 1 0 0 0
0 0 1 0 0