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How to make an identity matrix in Octave

In this lesson I'll explain how to make an identity matrix in Octave

What is an identity matrix? It is a square matrix composed of the same number of rows and columns with unitary values (1) in the main diagonal and zero (0) elsewhere. For example $$ I = \begin{pmatrix} 1 & 0 & 0 \\ 0 & 1 & 0 \\ 0 & 0 & 1 \end{pmatrix} $$

I'll give you a practical example.

To create an identity matrix of dimension 2 (two rows and two columns) use the eye() function.

>> eye(2)

The result is an identity matrix with two rows and two columns

ans =
Diagonal Matrix
1 0
0 1

If you want to create an identity matrix with three rows and three columns type eye(3)

>> eye(3)

The result is an identity matrix of dimension 3

ans =
Diagonal Matrix
1 0 0
0 1 0
0 0 1

The eye () function allows you to define an identity matrix of any size.

You can also use the eye(m, n) function to create a rectangular matrix with m rows and n columns that includes an identity submatrix.

For example, type eye(2,3) to create a 2x3 matrix with an identity matrix inside it

>> eye(2,3)

The result is a 2x3 rectangular matrix with a 2x2 identity matrix as a square submatrix.

ans =
Diagonal Matrix
1 0 0
0 1 0




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