fact: Variables (A B : finType) (W : `Ch*(A, B)).
imports: mathcomp(all_ssreflect ssralg matrix) Reals mathcomp(Rstruct) ssrR Reals_ext ssr_ext ssralg_ext logb ln_facts num_occ fdist entropy types jtypes divergence conditional_divergence error_exponent channel_code channel success_decode_bound