fact: Fixpoint de_casteljau (b : nat -> R) (n : nat) := match n with O => b | i.+1 => fun j => (l * de_casteljau b i j + r * de_casteljau b i j.+1)%R end.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat binomial seq choice order) mathcomp(fintype bigop ssralg poly ssrnum ssrint rat ssrnum) mathcomp(polyrcf qe_rcf_th realalg) pol poly_normal desc