#11239: Incorrect coercion of polynomials over finite fields
-------------------------------------+-------------------------------------
Reporter: johanbosman | Owner: robertwb
Type: defect | Status: needs_info
Priority: major | Milestone: sage-6.1
Component: coercion | Resolution:
Keywords: finite fields, | Merged in:
polynomials, coercion, sd53 | Reviewers: Jean-Pierre Flori
Authors: Peter Bruin | Work issues:
Report Upstream: N/A | Commit:
Branch: | 236effb6198c6192dce0cedc0e53423c68743e3e
u/jpflori/ticket/11239 | Stopgaps:
Dependencies: #8335 |
-------------------------------------+-------------------------------------
Comment (by pbruin):
Replying to [comment:21 jpflori]:
> Maybe this is worth a broader discussion on sage-devel...
I think it is worth thinking about whether the "stupid" conversion should
be allowed between different quotients of a polynomial ring. However, for
the problem addressed in this ticket, there is really only one sensible
thing to do, namely applying the canonical map between the base rings.
> Especially, should we let the stupid conversion in when there is no
coercion (as it seems to fit Sage's philosophy and it is in place for
quotients)?
I personally think that allowing `Fqq['y'](f)` to 'desperately' apply any
available conversion, however nonsensical it may be, to the coefficients
is a bad idea. I don't see what is gained by permitting this notation; it
seems to make it far too easy for the user to unwittingy introduce
mysterious errors in this way. If someone really wants this behaviour, it
is much better to require explicitly lifting the finite field elements to
'''Z'''[''x''] or another suitable ring.
I would be in favour of a less permissive approach for conversions between
different polynomial ring quotients as well, but again, this ticket is not
the place to decide that.
--
Ticket URL: <http://trac.sagemath.org/ticket/11239#comment:23>
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 unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
Visit this group at http://groups.google.com/group/sage-trac.
For more options, visit https://groups.google.com/groups/opt_out.
