The equalities (first graph Phi) * Phi == last graph Phi and (first graph Phi)^-1 * (last graph Phi) == Phi are always satisfied.
i1 : ZZ/333331[x_0..x_4]; |
i2 : Phi = multirationalMap {rationalMap(minors(2,matrix{{x_0..x_3},{x_1..x_4}}),Dominant=>true)} o2 = Phi o2 : MultirationalMap (dominant rational map from PP^4 to hypersurface in PP^5) |
i3 : time (Phi1,Phi2) = graph Phi -- used 0.303552 seconds o3 = (Phi1, Phi2) o3 : Sequence |
i4 : Phi1; o4 : MultirationalMap (birational map from 4-dimensional subvariety of PP^4 x PP^5 to PP^4) |
i5 : Phi2; o5 : MultirationalMap (dominant rational map from 4-dimensional subvariety of PP^4 x PP^5 to hypersurface in PP^5) |
i6 : time (Phi21,Phi22) = graph Phi2 -- used 0.882578 seconds o6 = (Phi21, Phi22) o6 : Sequence |
i7 : Phi21; o7 : MultirationalMap (birational map from 4-dimensional subvariety of PP^4 x PP^5 x PP^5 to 4-dimensional subvariety of PP^4 x PP^5) |
i8 : Phi22; o8 : MultirationalMap (dominant rational map from 4-dimensional subvariety of PP^4 x PP^5 x PP^5 to hypersurface in PP^5) |
i9 : time (Phi211,Phi212) = graph Phi21 -- used 6.65398 seconds o9 = (Phi211, Phi212) o9 : Sequence |
i10 : Phi211; o10 : MultirationalMap (birational map from 4-dimensional subvariety of PP^4 x PP^5 x PP^5 x PP^4 x PP^5 to 4-dimensional subvariety of PP^4 x PP^5 x PP^5) |
i11 : Phi212; o11 : MultirationalMap (birational map from 4-dimensional subvariety of PP^4 x PP^5 x PP^5 x PP^4 x PP^5 to 4-dimensional subvariety of PP^4 x PP^5) |
i12 : assert( source Phi1 == source Phi2 and target Phi1 == source Phi and target Phi2 == target Phi and source Phi21 == source Phi22 and target Phi21 == source Phi2 and target Phi22 == target Phi2 and source Phi211 == source Phi212 and target Phi211 == source Phi21 and target Phi212 == target Phi21) |
i13 : assert(Phi1 * Phi == Phi2 and Phi21 * Phi2 == Phi22 and Phi211 * Phi21 == Phi212) |