Cookbooks
Rust
Chapter 3. Numbers
Working with complex numbers

Rust:
Working with complex numbers

How to:

Rust doesn’t have built-in complex number support, but crates like num-complex have your back. Here’s how to use it:

use num_complex::Complex;

fn main() {
    let a = Complex::new(2.0, 3.0); // 2 + 3i
    let b = Complex::new(1.0, -4.0); // 1 - 4i

    let sum = a + b;
    let product = a * b;

    println!("Sum: {}", sum); // Sum: 3 - 1i
    println!("Product: {}", product); // Product: 14 - 5i
}

You’ll need to add num_complex to your Cargo.toml to make this magic happen.

Deep Dive

Complex numbers were conceived in the 16th century but really took off in the 18th century when mathematicians like Euler started playing with them.

Without native complex number operations, languages like Rust rely on third-party libraries. num-complex is one such crate and is part of the num crate collection that aims to provide numeric types and traits for Rust.

It’s worth mentioning that some languages (like Python) have built-in support for complex numbers, while others (like C++, with the <complex> header) provide them as part of the standard library. In Rust, the decision to keep the standard library small means you’ll often reach for community-created crates for additional functionality.

See Also

Rounding numbers