Scalar Matrix

A scalar matrix is a square matrix where each entry on the main diagonal holds the same constant value (other than zero), while all off-diagonal elements are zero.

Formula for scalar matrix:

In other words, it’s a specific type of diagonal matrix with identical values along the main diagonal.

Example: The matrix below is an example of a scalar matrix.
Example of scalar matrix

A scalar matrix is formed by multiplying the identity matrix by a constant.

This type of matrix can always be expressed as a multiple of the identity matrix.

Given a scalar value α, a scalar matrix is simply the product of α and the identity matrix I.

Scalar matrix is equal to the scalar multiplied by the identity matrix

    Properties of Scalar Matrices

    Scalar matrices exhibit a unique property: they retain the commutative property under matrix multiplication.

    For any real number α, scalar matrix I(n), and matrix A, the product α·I(n)·A equals α·A·I(m), resulting in the scalar product α·A in both cases.

    Commutativity of matrix

    Example: A practical application of scalar matrices.
    Practical example

     
     

    Please feel free to point out any errors or typos, or share suggestions to improve these notes. English isn't my first language, so if you notice any mistakes, let me know, and I'll be sure to fix them.

    FacebookTwitterLinkedinLinkedin
    knowledge base

    Matrices (linear algebra)