fact: Definition type_of_row (a : A) (Ha : N(a | ta) != 0) : P_ N(a | ta) ( B ).
imports: mathcomp(all_ssreflect ssralg ssrnum fingroup perm) Reals mathcomp(Rstruct) ssrR Reals_ext realType_ext ssr_ext ssralg_ext logb fdist entropy num_occ channel types