fact: Structure addv_expr := Sumv { addv_val :> wrapped {vspace vT}; addv_dim : wrapped nat; _ : mxsum_spec (vs2mx (unwrap addv_val)) (unwrap addv_dim) }.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype bigop finfun tuple) mathcomp(ssralg matrix mxalgebra zmodp)