fact: Definition funeneg T (R : realDomainType) (f : T -> \bar R) := fun x => maxe (- f x) 0.
imports: HB(structures) mathcomp(all_ssreflect ssralg ssrnum ssrint interval finmap) mathcomp(mathcomp_extra boolp classical_sets fsbigop) mathcomp(functions cardinality set_interval) signed reals ereal topology normedtype sequences