#12236: random element madness
--------------------------------+-------------------------------------------
Reporter: mariah | Owner: swenson
Type: defect | Status: new
Priority: minor | Milestone: sage-5.0
Component: basic arithmetic | Keywords:
Work_issues: | Upstream: N/A
Reviewer: | Author:
Merged: | Dependencies:
--------------------------------+-------------------------------------------
Changes (by swenson):
* owner: AlexGhitza => swenson
Comment:
I have a patch to address some of this that I will post as soon as I can,
but there are two issues here, which are identified above.
Issue 1 is a "feature" of QuotientRing_generic that I am still getting to
the bottom of, but notice, here
This appears to be related to the following error:
{{{
sage: ZZ['x'].quotient(2 * ZZ)
...
TypeError: polynomial must have unit leading coefficient
}}}
i.e., polynomial rings seem to expect that, if you mod out by an ideal, it
should be a polynomial, which isn't the case if you are trying to mod out
by an ideal in the base ring.
This seems to raise other issues with integer ideals interacting with
polynomials rings, e.g.,
{{{
sage: ZZ['x'].quotient(ZZ['x'].ideal([x^4 + 1, 2])).quotient(2)
Quotient of Univariate Polynomial Ring in x over Integer Ring by the ideal
(2, x^4 + 1, 2)
sage: ZZ['x'].quotient(ZZ['x'].ideal([x^4 + 1, 2])).quotient(2)(2)
2
}}}
:(
Issue 2 raised above has to do with ideal.reduce(): the default
implementation is being called, which just gives a pass-through, i.e.,
{{{
sage: Integers(2).ideal().reduce(2)
2
}}}
At the very least, this should be coercing its argument into its base
ring.
--
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/12236#comment:1>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
--
You received this message because you are subscribed to the Google Groups
"sage-trac" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/sage-trac?hl=en.
