i1 : Phi = rationalMap(PP_(ZZ/333331)^(1,4),Dominant=>true)
o1 = Phi
o1 : MultirationalMap (dominant rational map from PP^4 to hypersurface in PP^5)

i2 : time (Phi1,Phi2) = graph Phi
 used 0.0399778s (cpu); 0.0387677s (thread); 0s (gc)
o2 = (Phi1, Phi2)
o2 : Sequence

i3 : Phi1;
o3 : MultirationalMap (birational map from 4dimensional subvariety of PP^4 x PP^5 to PP^4)

i4 : Phi2;
o4 : MultirationalMap (dominant rational map from 4dimensional subvariety of PP^4 x PP^5 to hypersurface in PP^5)

i5 : time (Phi21,Phi22) = graph Phi2
 used 0.237111s (cpu); 0.112976s (thread); 0s (gc)
o5 = (Phi21, Phi22)
o5 : Sequence

i6 : Phi21;
o6 : MultirationalMap (birational map from 4dimensional subvariety of PP^4 x PP^5 x PP^5 to 4dimensional subvariety of PP^4 x PP^5)

i7 : Phi22;
o7 : MultirationalMap (dominant rational map from 4dimensional subvariety of PP^4 x PP^5 x PP^5 to hypersurface in PP^5)

i8 : time (Phi211,Phi212) = graph Phi21
 used 0.391604s (cpu); 0.277046s (thread); 0s (gc)
o8 = (Phi211, Phi212)
o8 : Sequence

i9 : Phi211;
o9 : MultirationalMap (birational map from 4dimensional subvariety of PP^4 x PP^5 x PP^5 x PP^4 x PP^5 to 4dimensional subvariety of PP^4 x PP^5 x PP^5)

i10 : Phi212;
o10 : MultirationalMap (birational map from 4dimensional subvariety of PP^4 x PP^5 x PP^5 x PP^4 x PP^5 to 4dimensional subvariety of PP^4 x PP^5)

i11 : 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)

i12 : assert(Phi1 * Phi == Phi2 and Phi21 * Phi2 == Phi22 and Phi211 * Phi21 == Phi212)
