Pullback -- pullback in the category of rings
Pullback is a package that implements pullback for diagrams of rings
Works only for maps of rings finitely generated over a base field and one of the two maps is surjective
This documentation describes version 1.03 of Pullback.
The source code from which this documentation is derived is in the file Pullback.m2.
Functions and commands
"internalUseDirectSum(Ring,Ring)" -- see internalUseDirectSum -- Compute direct sum of two rings.
"pullback(RingMap,RingMap)" -- see pullback -- Compute the pullback of a diagram of rings