Method commit

poly-commit/src/kzg10/mod.rs:157–210

Outputs a commitment to `polynomial`. # Examples ``` use ark_poly_commit::kzg10::{KZG10, Powers}; use ark_bls12_381::Bls12_381; use ark_bls12_381::Fr; use ark_poly::DenseUVPolynomial; use ark_poly::univariate::DensePolynomial; use ark_ec::pairing::Pairing; use ark_ec::AffineRepr; use ark_std::test_rng; use ark_std::Zero; type UniPoly_381 = DensePolynomial< ::ScalarField>; l

(
        powers: &Powers<E>,
        polynomial: &P,
        hiding_bound: Option<usize>,
        rng: Option<&mut dyn RngCore>,
    )

    /// assert!(!r.is_hiding(), "Commitment should not be hiding");
    /// ```
    pub fn commit(
        powers: &Powers<E>,
        polynomial: &P,
        hiding_bound: Option<usize>,
        rng: Option<&mut dyn RngCore>,
    ) -> Result<(Commitment<E>, Randomness<E::ScalarField, P>), Error> {
        Self::check_degree_is_too_large(polynomial.degree(), powers.size())?;

        let commit_time = start_timer!(|| format!(
            "Committing to polynomial of degree {} with hiding_bound: {:?}",
            polynomial.degree(),
            hiding_bound,
        ));

        let (num_leading_zeros, plain_coeffs) =
            skip_leading_zeros_and_convert_to_bigints(polynomial);

        let msm_time = start_timer!(|| "MSM to compute commitment to plaintext poly");
        let mut commitment = <E::G1 as VariableBaseMSM>::msm_bigint(
            &powers.powers_of_g[num_leading_zeros..],
            &plain_coeffs,
        );
        end_timer!(msm_time);

        let mut randomness = Randomness::<E::ScalarField, P>::empty();
        if let Some(hiding_degree) = hiding_bound {
            let mut rng = rng.ok_or(Error::MissingRng)?;
            let sample_random_poly_time = start_timer!(|| format!(
                "Sampling a random polynomial of degree {}",
                hiding_degree
            ));

            randomness = Randomness::rand(hiding_degree, false, None, &mut rng);
            Self::check_hiding_bound(
                randomness.blinding_polynomial.degree(),
                powers.powers_of_gamma_g.len(),
            )?;
            end_timer!(sample_random_poly_time);
        }

        let random_ints = convert_to_bigints(&randomness.blinding_polynomial.coeffs());
        let msm_time = start_timer!(|| "MSM to compute commitment to random poly");
        let random_commitment = <E::G1 as VariableBaseMSM>::msm_bigint(
            &powers.powers_of_gamma_g,
            random_ints.as_slice(),
        )
        .into_affine();
        end_timer!(msm_time);

        commitment += &random_commitment;

        end_timer!(commit_time);
        Ok((Commitment(commitment.into()), randomness))
    }

    /// Compute witness polynomial.
    ///