fact: Definition head_root (f : R -> R) (l : seq (root_info R)) : Prop := match l with [::] => True | Exact x::tl => True | One_in x y::tl => f x != 0 | Zero_in x y::tl => f x != 0 | Unknown x y::tl => f x != 0 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