"Source: Text/Geometry/AlgSrf.text";
"Line: 5049";
"Date: Mon Mar 29 22:30:18 2021";
"Main: Thu May 25 10:02:38 2023";
// original file: Text/Geometry/AlgSrf.text, line: 5049
// Example: H123E27 ()
print "Example: H123E27";
ei := GetEchoInput();
SetEchoInput(true);
Q := Rationals();
P2<X,Y,W> := ProjectiveSpace(Q, 2);
P3<x,y,z,w> := ProjectiveSpace(Q, 3);
X1 := Scheme(P3, x^2 + y^2 + z^2 + w^2);
X2 := Scheme(P3, x^2 + y^2 + z^2 - w^2);
X3 := Scheme(P3, x^2 + y^2 + z^2);
X4 := Scheme(P3, x^2 + y^2 - z^2);
X5 := Scheme(P3, x^2 - 4*x*z + 3*x*w + y*z - y*w + 2*z^2
                  - 3*z*w + w^2);
ParametrizeQuadric(X1, P2);
assert not $1;
ParametrizeQuadric(X2, P2);
ParametrizeQuadric(X3, P2);
assert not $1;
ParametrizeQuadric(X4, P2);
ParametrizeQuadric(X5, P2);
SetEchoInput(ei);
