练习：几何图形

我们将为三维几何图形创建几个实用函数，将点表示为 [f64;3]。函数签名由您自行确定。

// Calculate the magnitude of a vector by summing the squares of its coordinates
// and taking the square root. Use the `sqrt()` method to calculate the square
// root, like `v.sqrt()`.
fn magnitude(...) -> f64 {
    todo!()
}
// Normalize a vector by calculating its magnitude and dividing all of its
// coordinates by that magnitude.
fn normalize(...) {
    todo!()
}
// Use the following `main` to test your work.
fn main() {
    println!("Magnitude of a unit vector: {}", magnitude(&[0.0, 1.0, 0.0]));
    let mut v = [1.0, 2.0, 9.0];
    println!("Magnitude of {v:?}: {}", magnitude(&v));
    normalize(&mut v);
    println!("Magnitude of {v:?} after normalization: {}", magnitude(&v));
}