Function libra_eval 

pub fn libra_eval<F: FieldOps>(
    challenge_point: &[F],
    query_j: &[F],
    query_k: &[F],
    n_vars: usize,
    degree: usize,
) -> F

Evaluates the MLE of the libra_eval polynomial at a query point.

Computes the multilinear extension of libra_eval_r at the query point (query_j, query_k):

Σⱼ Σₖ eq(j, query_j) · eq(k, query_k) · r[j]^k

for j < n_vars and k ≤ degree, where eq is the equality indicator polynomial.

Arguments

• challenge_point - The challenge point r from sumcheck (length n_vars)
• query_j - Query point for the variable index (length m_n)
• query_k - Query point for the power index (length m_d)
• n_vars - Number of variables in the mask polynomial
• degree - Degree of each univariate in the mask polynomial