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MultiprojectiveVarieties :: check(MultirationalMap)

check(MultirationalMap) -- check that a multi-rational map is well-defined

Synopsis

Description

i1 : ZZ/65521[x_0..x_4], f = rationalMap {x_3^2-x_2*x_4,x_2*x_3-x_1*x_4,x_1*x_3-x_0*x_4,x_2^2-x_0*x_4,x_1*x_2-x_0*x_3,x_1^2-x_0*x_2};
i2 : Phi = multirationalMap {f}

o2 = Phi

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

o3 = Phi

o3 : MultirationalMap (rational map from PP^4 to PP^5)
i4 : Y = image Phi

o4 = Y

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

o5 = Psi

o5 : MultirationalMap (rational map from PP^4 to hypersurface in PP^5)
i6 : check Psi

o6 = Psi

o6 : MultirationalMap (rational map from PP^4 to hypersurface in PP^5)
i7 : p = point Y;

o7 : ProjectiveVariety, 0-dimensional subvariety of PP^5
i8 : Eta = multirationalMap({f},p);

o8 : MultirationalMap (rational map from PP^4 to 0-dimensional subvariety of PP^5)
i9 : try check Eta else <<"meaningless object!";
meaningless object!