Macaulay2 » Documentation
Packages » A1BrouwerDegrees :: getBaseField

next | previous | forward | backward | up | index | toc

getBaseField -- the base field of a Grothendieck-Witt class

Usage:

getBaseField beta
Inputs:
- beta, a Grothendieck-Witt Class, the isomorphism class of a non-degenerate symmetric bilinear form over a field of characteristic not 2
Outputs:
- a ring, the base field of the Grothendieck-Witt class beta

Description

Given the isomorphism class of a symmetric bilinear form, beta, this command outputs the base field of the form.

i1 : beta = makeGWClass matrix(QQ, {{0,2},{2,0}});

i2 : getBaseField beta

o2 = QQ

o2 : Ring

See also

GrothendieckWittClass -- a new type, intended to capture the isomorphism class of an element of the Grothendieck-Witt ring of a base field

Ways to use getBaseField:

getBaseField(GrothendieckWittClass)

For the programmer

The object getBaseField is a method function.

The source of this document is in A1BrouwerDegrees/Documentation/GrothendieckWittClassesDoc.m2:105:0.