Function winter_math::polynom::sub

pub fn sub<E>(a: &[E], b: &[E]) -> Vec<E>
where
    E: FieldElement,

Returns a polynomial resulting from subtracting one polynomial from another.

Specifically, subtracts polynomial b from polynomial a and returns the result. Both polynomials are expected to be in the coefficient form, and the returned polynomial will be in the coefficient form as well. The length of the returned vector will be max(a.len(), b.len()).

Examples

// p1(x) = 4 * x^2 + 3 * x + 2
let p1 = (2_u32..5).map(BaseElement::from).collect::<Vec<_>>();
// p2(x) = 2 * x + 1
let p2 = (1_u32..3).map(BaseElement::from).collect::<Vec<_>>();

// expected result = 4 * x^2 + x + 1
let expected = vec![
    BaseElement::new(1),
    BaseElement::new(1),
    BaseElement::new(4),
];
assert_eq!(expected, sub(&p1, &p2));