proposition: Lemma fdist_lt1 d a : (d a != 1) <-> (d a < 1).
proof: Proof. split=> H; first by rewrite lt_neqAle H /=. by rewrite lt_eqF. Qed.
imports: mathcomp(all_ssreflect ssralg fingroup perm matrix) mathcomp(all_algebra vector reals normedtype) mathcomp(mathcomp_extra boolp) mathcomp(Rstruct) ssrR logb realType_ext ssr_ext ssralg_ext bigop_ext