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MultiprojectiveVarieties :: isWellDefined(MultirationalMap)

isWellDefined(MultirationalMap) -- whether a multi-rational map is well-defined

Synopsis

Description

i1 : f = rationalMap ideal PP_(ZZ/65521)^(1,4);

o1 : RationalMap (quadratic rational map from PP^4 to PP^5)
i2 : Phi = rationalMap {f}

o2 = Phi

o2 : MultirationalMap (rational map from PP^4 to PP^5)
i3 : isWellDefined Phi

o3 = true
i4 : Y = image Phi

o4 = Y

o4 : ProjectiveVariety, hypersurface in PP^5
i5 : Psi = rationalMap({f},Y)

o5 = Psi

o5 : MultirationalMap (rational map from PP^4 to Y)
i6 : isWellDefined Psi

o6 = true
i7 : p = point Y;

o7 : ProjectiveVariety, a point in PP^5
i8 : Eta = rationalMap({f},p);

o8 : MultirationalMap (rational map from PP^4 to p)
i9 : isWellDefined Eta

o9 = false

See also