clean ring mapping code in Primdec::zeroRad

[kroeker@…]

To get clean ring code in Primdec::zeroRad() (no hard-coding of variable names) new mapping or ring functionality is required.

The situation: from a ring R with k parameters and l variables a map is required to a ring S with k+l+m variables (with same coefficient field but different(?) ordering) and vice versa, while e.g. mapping k parameters in R to first k variables in S and the l variables in R to next l variables in S, (starting at position k+1)

The problem can be solved at least by two different approaches:

a)

provide a mapping function which maps the k parameters of R to first k variables in a Ring S and which maps the l variables in S to the k+1,...k+l variables in S

b)

1) provide a function which returns a new variable name VN, which is not in conflict with parameters and variables in R. 2) create the ring S reusing parameter and variable names from R, and also with new additional m variables VN(1..m) 3) use imap

Steps:

1. Decide, which variant should be implemented
2. Do it (I could provide a proposal for (b) )