Less permissive ring creation

[Jean-Pierre Flori]

Dear all,

I encountered the following issue in mprimdec.lib::GTZmod:
https://github.com/Singular/Sources/blob/spielwiese/Singular/LIB/mprimdec.lib#L635
execute("ring Rloc=("+charstr(basering)+","+varstr(basering)+"),dummy,("+ordstr(basering)+");");

In my case it is:
ring basering = 0,(x,y,z),dp;
which gives
ring Rloc = (0,x,y,z), dummy,(dp(3),C);

Singular 3.x used to accept this and applied dp to the sole variable dummy.
But now Singular 4.x complains that dp(3) wants 3 variables.

So two things:
* Singular behavior changed, and this makes sense to me, although one might want to apply the same ordering to a ring with more variables and cannot directly use ordstr for that anymore,
* not sure what is intended in the Rloc creation regarding ordering, so I have no idea how to properly fix it.

Best,
JP

[Jean-Pierre Flori]

I modified mprimdec.lib to use (C,dp) as in other places in the file.
Here is my patch:
https://git.sagemath.org/sage.git/diff/build/pkgs/singular/patches/mprimdec.patch?h=457bd233fc051f4ec6f8acf48dbf271af6d5bb46&id=dcd4e1454c917f8cd9a89c59a77421a08d798868
Feel free to use it.

[Jean-Pierre Flori]

Any chance to fix that one?
(By the way, I'm in KL right now if you want to discuss it face to face.)

[han...@mathematik.uni-kl.de]

it is now included: see 6d80671f0368807c17616b668161db9c22192314