  The Zps-additive codes of length n are subgroups of Zps^n , and can be seen
as a generalization of linear codes over Z2, Z4, or more general over Z2s . In
this paper, we show two methods for computing a parity-check matrix of a
Zps-additive code from a generator matrix of the code in standard form. We also
compare the performance of our results implemented in Magma with the current
available function in Magma for codes over finite rings in general. A time
complexity analysis is also shown.
