id summary reporter owner description type status priority milestone component resolution keywords cc merged author reviewer upstream work_issues branch commit dependencies stopgaps
16993 Broken fraction field of rational polynomial ring SimonKing "{{{
sage: P. = QQ[]
sage: p = 4/(-4*t)
sage: p # OK, fractions are not automatically reduced
4/(-4*t)
sage: p.reduce()
sage: p # What the heck...
4/(-4*t)
sage: p == -1/t # At least sage gets this right
True
}}}
So, not only is the fraction not automatically simplified by ""obvious"" common factors, but also it is not simplified upon request.
Note that the fraction field of an integral polynomial ring works better.
{{{
sage: P. = ZZ[]
sage: p = 4/(-4*t)
sage: p
1/-t
}}}
Fixed by #16268." defect closed major sage-duplicate/invalid/wontfix commutative algebra invalid tscrim yzh mkoeppe etn40ff slelievre Marc Mezzarobba N/A