In this recipe, we will explain how you can benchmark your code and how code benchmarking can be used to improve its efficiency.

We will show how to benchmark a simple function that takes a single argument in the form of an integer, `n`

, creates a random 10 x 10 matrix of floats, `A`

, and then calculates the norm of a product of this matrix by a random vector, `x`

. The sampling of `x`

should be performed `n`

times and the result of the function should be an `n`

-element vector of calculated norms.

Before we start, please make sure that you have the `BenchmarkTools`

package installed. If it is missing, then add it using the following commands: `using Pkg; Pkg.add("BenchmarkTools")`

.

### Note

In the GitHub repository for this recipe, you will find the `commands.txt`

file, which contains the presented sequence of shell and Julia commands.

Now, open your favorite terminal to execute the commands.