proposition: Lemma fdist_col'E v : fdist_col' v = \sum_(x : 'rV[A]_n.+1 | col' i x == v) P x.
proof: Proof. by rewrite fdistmapE. 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