id summary reporter owner description type status priority milestone component resolution keywords cc merged author reviewer upstream work_issues branch commit dependencies stopgaps
23185 A polynomial ring embeds into its fraction field saraedum "Currently, this fails:
{{{
sage: R. = QQ[]
sage: K. = FunctionField(QQ)
sage: R.is_subring(K)
NotImplementedError
sage: R.is_subring(R.fraction_field())
NotImplementedError
}}}
but it should return `True`.
The latter could be implemented in the category of ring homomorphisms (to find out whether a map is a coercion, just ask for the coercion between those two rings.)" defect closed minor sage-8.0 commutative algebra fixed sd86.5, sd87 Julian Rüth Marc Masdeu, David Roe N/A fa2dcd05df27798908cb39eb734da8ff4a36c63e fa2dcd05df27798908cb39eb734da8ff4a36c63e #23167, #23204