proposition: Lemma cpr_in_pairCr E F G : `Pr[ X \in E | [% Y, Z] \in F `* G ] = `Pr[ X \in E | [% Z, Y] \in G `* F ].
proof: Proof. rewrite 2!cpr_inE. rewrite pr_in_pairA pr_in_pairAC -pr_in_pairA; congr (_ / _). by rewrite pr_in_pairC. Qed.
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