# Machine Learning- Matrix-Vector Multiplication

We map the column of the vector onto each row of the matrix, multiplying each element, and summing the result. The result is a **vector**.

The number of columns of the matrix must equal the number of rows of the vector.An m x n matrix multiplied by an n x 1 vector results in an m x 1 vector.

The detailed explanation is given below:-

Example:-

Below is an example of matrix-vector multiplication. Make sure you understand how the multiplication works. Feel free to try different matrix-vector multiplications.

The output will be as follow:

Let’s have a look at how it helps in machine learning problems-