On completely regular and completely transitive supplementary codes

Given a parity-check matrix H-m of a q-ary Hamming code, we consider a partition of the columns into two subsets. Then, we consider the two codes that have these submatrices as parity-check matrices. We say that anyone of these two codes is the supplementary code of the other one. We obtain that if one of these codes is a Hamming code, then the supplementary code is completely regular and completely transitive. If one of the codes is completely regular with covering radius 2, then the supplementary code is also completely regular with covering radius at most 2. Moreover, in this case, either both codes are completely transitive, or both are not. With this technique, we obtain infinite families of completely regular and completely transitive codes which are quasi-perfect uniformly packed. (C) 2019 Elsevier B.V. All rights reserved.