`desing/coverx`
Performing a cover operation then exchange operations in the new
charts.
- Input:
-
- O, CP
- the same as of
`design/cover`,
- EXP
- a list of polynomials from k[S], representatives for the
elements to be put into the IND member of the charts,
- POSP
- a list of indices to IND, the positions where the
exchange has to be performed,
- Z
- output parameter, the list of singletons containing the
indices in the new charts that were eventually exchanged.
- Output:
- A list of chart-records, with the indicated exchanges
made.
The procedure functions like
`design/cover`, but it performs an
additional exchange operation on the new charts. The Z
parameter is necessary because the generators of CP might be
rearranged and some of them might be dropped, and we need to know
which polynomials were exchanged in the output charts.
The procedure adopts to the chosen representation of invertible
functions (determined by useDEP2).