Function vec2::angle

pub fn angle<T>(a: &[T; 2], b: &[T; 2]) -> T where
    T: Real,
    &'a T: Mul<&'b T, Output = T>, 

Example

use std::f32::consts::FRAC_PI_2;
let mut v: [f32; 2] = vec2::new_zero();
assert_eq!(vec2::angle(&[1_f32, 0_f32], &[0_f32, 1_f32]), FRAC_PI_2);