For computations which temporarily require a different term-ordering
(for example, to eliminate variables or to homogenize ideals), the
system automatically changes the term-ordering to a more suitable one,
performs the computation, and then restores the initial term-ordering
and gives its output with respect to this one. In this way the user
never has to deal with temporary changes.
Example
Use R ::= QQ[t,x,y,z];
I := Ideal(t-x,y-z,t-z);
Elim(y, I);
Ideal(t - z, -x + z)
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