fact: Fixpoint encompass_aux (l h : seq plane) : bool := match h with | nil => false | t1 :: nil => true | t1 :: ((t2 :: _) as h') => all_left t1 t2 l && encompass_aux l h' end.
imports: mathcomp(all_ssreflect all_algebra vector reals ereal classical_sets) mathcomp(zmodp) preliminaries preliminaries_hull axiomsKnuth