fact: Definition merge_intervals (ar1 ar2 : F * F) := let l := minr (ar1.1 - ar1.2) (ar2.1 - ar2.2) in let u := maxr (ar1.1 + ar1.2) (ar2.1 + ar2.2) in ((l + u) / 2%:R, (u - l) / 2%:R).
imports: mathcomp.ssreflect.ssreflect mathcomp(ssrfun ssrbool eqtype ssrnat seq choice fintype) mathcomp(bigop order ssralg ssrnum ssrint rat poly polydiv polyorder) mathcomp(perm matrix mxpoly polyXY binomial bigenough)