fact: Definition opp_reality_subdef (xnz : nullity) (xr : reality) : reality := match xr with | Real (Sign =0) => =0 | Real (Sign >=0) => <=0 | Real (Sign <=0) => >=0 | Real AnySign => >=<0 | Arbitrary => >?<0 end.
imports: HB(structures) Coq(ssreflect ssrfun ssrbool) mathcomp(ssrnat eqtype choice order ssralg ssrnum ssrint) mathcomp(mathcomp_extra)