proposition: Lemma big_beta_mul (A : finType) (F1 F2 : A -> R) (l : pred A) : \big[beta_op/(1,1)]_(i <- enum l) (F1 i, F2 i) = (\prod_(i in l) F1 i , \prod_(i in l) F2 i).
proof: Proof. rewrite /index_enum big_filter. elim: (Finite.enum A) => [|a la IH]. by rewrite !big_nil. rewrite !big_cons /=. by case Ha: (a \in l); rewrite IH. Qed.
imports: Wf_nat Init.Wf Recdef Reals mathcomp(all_ssreflect perm zmodp matrix ssralg) mathcomp(Rstruct) ssrR Reals_ext ssr_ext ssralg_ext bigop_ext f2 fdist channel pproba linearcode subgraph_partition tanner tanner_partition summary ldpc checksum ldpc_algo