proposition: Lemma measure_snum_subproof S : Signed.spec 0 ?=0 >=0 (mu S).
proof: Proof. exact: measure_ge0. Qed.
imports: mathcomp(all_ssreflect all_algebra finmap) mathcomp(mathcomp_extra boolp classical_sets functions) mathcomp(cardinality fsbigop ) reals ereal signed topology normedtype sequences esum numfun HB(structures)