fact: Definition inde_rv := forall (x : TA) (y : TB), `Pr[ [% X, Y] = (x, y)] = `Pr[ X = x ] * `Pr[ Y = y ].
imports: mathcomp(all_ssreflect ssralg ssrnum matrix) mathcomp(Rstruct reals) Reals Lra ssrR Reals_ext realType_ext logb ssr_ext ssralg_ext bigop_ext fdist