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RationalMaps :: isRegularMap

isRegularMap -- whether a map to projective space is regular

Synopsis

Description

This function runs baseLocusOfMap(f) and checks whether the ideal defining the base locus is the whole ring.

i1 : P5 = QQ[a..f];
i2 : P2 = QQ[x,y,z];
i3 : M = matrix{{a,b,c},{d,e,f}};

              2        3
o3 : Matrix P5  <--- P5
i4 : blowUpSubvar = P5/(minors(2, M) + ideal(b - d));
i5 : f = map(blowUpSubvar, P2, {a, b, c});

o5 : RingMap blowUpSubvar <--- P2
i6 : isRegularMap(f)

o6 = true

Ways to use isRegularMap :

For the programmer

The object isRegularMap is a method function with options.