Function poly_commitment::commitment::b_poly

pub fn b_poly<F: Field>(chals: &[F], x: F) -> F

Returns (1 + chal[-1] x)(1 + chal[-2] x^2)(1 + chal[-3] x^4) … It’s “step 8: Define the univariate polynomial” of appendix A.2 of https://eprint.iacr.org/2020/499