lp to dp

Hello

I want to compute the Groebner Basis in x > z > y from an Ideal like:
<z_i - f(x), y_i - g(x) >

if I choose lp on z the computation is fast and I get a result in 5 minutes.
But if I choose dp on z the computation takes a lot more time (> 3h).
Unfortunately I need dp on z, so maybe there is a way to transform from lp to dp in short time?

thanks

To convert a Groebner basis from one oredering to another
you can use fglm (for zero dimensional ideals)
or use the Hilbert function to speed up the computation:

ring r1=....;
ideal I=....;
ideal J=groebner(I);
intvec h=hilb(J,1);
ring r2=.....;
ideal I=fetch(r1,I);
ideal J=std(I,h);

Hans Schoenemann, Singular team