proposition: Lemma eseries_mkcond [R : realFieldType] [P : pred nat] (f : nat -> \bar R) : \sum_(i <oo | P i) f i = \sum_(i <oo) if P i then f i else 0.
proof: Proof. by apply/congr_lim/eq_fun => n /=; apply: big_mkcond. Qed.
imports: mathcomp(all_ssreflect ssralg ssrint ssrnum matrix) mathcomp(interval rat) mathcomp(mathcomp_extra boolp classical_sets functions) mathcomp(set_interval) reals ereal signed topology normedtype landau