Function sp_arithmetic::biguint::mul_single

pub fn mul_single(a: Single, b: Single) -> Double

Assumed as a given primitive.

Multiplication of two singles, which at most yields 1 double.

Examples found in repository

src/biguint.rs (line 275)

	pub fn mul(self, other: &Self) -> Self {
		let n = self.len();
		let m = other.len();
		let mut w = Self::with_capacity(m + n);

		for j in 0..n {
			if self.get(j) == 0 {
				// Note: `with_capacity` allocates with 0. Explicitly set j + m to zero if
				// otherwise.
				continue
			}

			let mut k = 0;
			for i in 0..m {
				// PROOF: (B−1) × (B−1) + (B−1) + (B−1) = B^2 −1 < B^2. addition is safe.
				let t = mul_single(self.get(j), other.get(i)) +
					Double::from(w.get(i + j)) +
					Double::from(k);
				w.set(i + j, (t % B) as Single);
				// PROOF: (B^2 - 1) / B < B. conversion is safe.
				k = (t / B) as Single;
			}
			w.set(j + m, k);
		}
		w
	}