Feature #50
Polynomial content
Description
New function(s) to compute content of a poly w.r.t. a given indet.
In which ring does the result lie?- if poly is univariate, result will be in coeff ring
- if poly is multivariate, result may be in poly ring
DECIDE!!!
May want an extended version which computes content w.r.t to several indets?
Related issues
History
#1
Updated by John Abbott about 12 years ago
Updated by - % Done changed from 0 to 60
Created two fns:
contentcomputes "content" of the coeffs, result is in CoeffRingContentWRTcomputes "content" wrt given indets, result is in original poly ring.
Must still add doc, and tests.
#2
Updated by Anna Maria Bigatti almost 12 years ago
Updated by Tests and doc are already done for CoCoA-5.
Still missing in CoCoALib
#3
Updated by John Abbott almost 12 years ago
- % Done changed from 60 to 90
The function ContentWRT gives result with strange scale factors sometimes.
Use ZZ/(29641)[x,y]; f := (2*x+3)*(3*y+2); ContentWRT(f,x); -6*y -4
Perhaps make the result monic? Note (2013-05-27) the monic answer is y+9881 do we really want that?
Seems to be well behaved in QQ[x,y].
#4
Updated by Anna Maria Bigatti over 11 years ago
- Status changed from New to Feedback
- Target version set to CoCoALib-0.9953
#5
Updated by John Abbott almost 11 years ago
- Status changed from Feedback to Closed
- Assignee set to John Abbott
- % Done changed from 90 to 100
The main issue has been satisfactorily resolved for a year or so.
The question about "normalization" (in post 3) is really the same as issue #154 about normalization of the result of GCD computations, so I shall ignore it here, and regard the issue as closed now.