Function gaxpy 

pub fn gaxpy<T: Numeric<T>>(a_mat: &Sprs<T>, x: &[T], y: &[T]) -> Vec<T>

Generalized A times X Plus Y

r = A * x + y

Example

let a = [
    vec![0., 0., 2.],
    vec![1., 0., 0.],
    vec![9., 9., 9.]
];
let mut a_sparse = rsparse::data::Sprs::new();
a_sparse.from_vec(&a);

let x = vec![1., 2., 3.];
let y = vec![3., 2., 1.];

assert_eq!(rsparse::gaxpy(&a_sparse, &x, &y), vec![9., 3., 55.]);