fact: Definition fun_of_lfun_def aT rT (f : 'Hom(aT, rT)) := r2v \o mulmxr (f2mx f) \o v2r.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype bigop finfun tuple) mathcomp(ssralg matrix mxalgebra zmodp)