Function norm 

pub fn norm<'out, T>(out: &'out mut [T; 2], b: &[T; 2]) -> T
where
    T: Real,
    for<'a, 'b> &'a T: Mul<&'b T, Output = T> + Div<&'b T, Output = T>,

Example

let mut v = vec2::new_zero::<f32>();
assert_eq!(vec2::norm(&mut v, &vec2::new_one()), 2_f32.sqrt());
assert_eq!(v, [1_f32 / 2_f32.sqrt(); 2]);