"Source: Text/Commut/RngDiff.text";
"Line: 2604";
"Date: Thu Sep 25 14:47:46 2025";
"Main: Fri Sep 26 14:29:19 2025";
// original file: Text/Commut/RngDiff.text, line: 2604
// Example: H121E46 ()
print "Example: H121E46";
ei := GetEchoInput();
SetEchoInput(true);
F<z> := RationalDifferentialField(Rationals());
R<D> := DifferentialOperatorRing(F);
df := Differential(z^3+5);
RM<DM>, mp := ChangeDifferential(R,df);
Domain(mp) eq R and Codomain(mp) eq RM;
assert $1;
M<u> := BaseRing(RM);
IsDifferentialOperatorRing(RM) and IsAlgebraicDifferentialField(M);
assert $1;
mp(RM!z);
mp(D);
D*z, mp(D*z);
DM*u;
Differential(RM);
SetEchoInput(ei);
