Feature #978
CommonDenom: for polys and lists?
Status:
Closed
Priority:
Normal
Assignee:
Category:
CoCoA-5 function: new
Target version:
Description
Should there be a function called CommonDenom
(or something similar)?
For polynomials? For lists of polynomials?
Related issues
History
#1 Updated by John Abbott over 7 years ago
In fact there is already an undocumented builtin fn called CommonDenom
, but only for RINGELEM. The fn also exists in CoCoALib (and is documented there).
What are the exact semantics? And what should they be?
Should the fn be extended to lists of RINGELEM? (also in CoCoALib?)
#2 Updated by John Abbott over 7 years ago
- Related to Support #977: "universal denominator" (related with GroebnerFanIdeals) added
#3 Updated by John Abbott over 7 years ago
Some aspects to consider when deciding the semantics:
- we may assume that the result is positive (if coeffs in
QQ
) - defn is clear in
QQ[x,y,z]
- should it also work for
QQ[a,b][x,y,z]
? - should it also work for
QQ(a,b)[x,y,z]
orFrF(ZZ[a,b])[x,y,z]
- should it work for an element of
QQ
or even ofZZ
?
If we make it work for lists of RINGELEM, should it be recursive (e.g. so it would work for list of list of RINGELEM)?
#4 Updated by Anna Maria Bigatti almost 7 years ago
- Target version changed from CoCoA-5.2.0 spring 2017 to CoCoA-5.2.2
- We are going to work on this, better postpone this.
#5 Updated by Anna Maria Bigatti over 6 years ago
- Target version changed from CoCoA-5.2.2 to CoCoA-5.2.4
Work on "ideals mod p" still in progress.
Postpone to next version.
#6 Updated by John Abbott almost 6 years ago
- Status changed from New to Resolved
- % Done changed from 0 to 80
This appears already to have been done (and documented).
Feedback? Close?
#7 Updated by Anna Maria Bigatti over 5 years ago
- Status changed from Resolved to Closed
- Assignee set to John Abbott
- % Done changed from 80 to 100
- Estimated time set to 1.01 h