fact: Definition phase_shift (v : 'rV[F]_n) mu : 'rV[F]_n := \row_i ((v ``_ i) * a ^+ (mu * i)).
imports: mathcomp(all_ssreflect ssralg poly polydiv zmodp) mathcomp(matrix mxalgebra mxpoly vector cyclic perm) ssr_ext ssralg_ext hamming