How to Get Absolute Value in Rust

In previous versions of Rust, the std::num::abs function was used to get the absolute value, but this function is no longer available. These days, the abs() function is utilized to return the absolute value of most of the number types.

This article will discuss using the abs() function to get the absolute value in Rust.

Use the abs() Function to Get Absolute Value in Rust

To get absolute value, we need to specify the data types explicitly. We also need to know that the suffix i tells Rust that the number in front of the suffix is an integer.

fn main(){
    let num = -29i32;
    let anum = num.abs();
    println!("{}",anum);
}

We defined an immutable variable num and assigned -29 to it. i32 refers to the 32-bit signed integer type.

Output:

29

As seen in the output, 29 is an absolute value. Let’s take a look at another example.

fn main() {
    let mut num1:i32 = -9;
    let mut num2:i32 = 16;
    let mut num:i32 = 0;

    num = num1.abs();
    println!(" The absolute value of num1: {}",num);

    num = num2.abs();
    println!("The absolute value of num2: {}",num);
}

We added mut right after let to make the variable mutable. Variable num1 is assigned -9, and num2 is assigned 16.

We will find the absolute value of num1 and num2 using the abs() function.

Output:

The absolute value of num1: 9
The absolute value of num2: 16

The output above shows that we got the absolute values of num1 and num2 as 9 and 16.