baseMap -- Returns the underlying RingMap of a WittRingMap

Description

Given a WittRingMap $W(f): W_n(R) \to W_n(S)$ induced by f:R-> S, this returns the underlying RingMap f: R->S.

i1 : R = (ZZ/5)[x,y];

i2 : S = (ZZ/5)[a,b,c,d];

i3 : f = map(S, R, {a*b, c*d});

o3 : RingMap S <-- R

i4 : Wf = witt(2, f);

i5 : f === baseMap Wf

o5 = true

The source of this document is in WittVectors/Documentation.m2:169:0.