another example for incomplete primdecSY() decomposition

[kroeker@…]

system("random",1947043918);
LIB("primdec.lib");
LIB("ehv.lib");
ring rng = (13931,vv),(xx,yy,zz,ww),dp;
minpoly = (vv^2-13);
ideal I = 5531*xx*zz^2+(1016*vv),(169*vv)*yy^2*ww+2197*xx,-3044*xx^2*ww+1362;
list L1 = primdecGTZ(I);
list L2 = primdecSY(I);

L1;
L2;

ASSUME(0, testPrimary( L1 , I ) );
ASSUME(0, testPrimary( L2 , I ) );

primDecsAreEquivalent(L1, L2);

output

. L1;
[1]:
   [1]:
      _[1]=yy*ww-3136*zz
      _[2]=zz^2+(723*vv)*xx*ww
      _[3]=yy*zz+(-3425*vv)*xx
      _[4]=xx^2*ww+2956
      _[5]=xx^2*zz+3537*yy
      _[6]=xx^3+(-1299*vv)*yy^2
   [2]:
      _[1]=yy*ww-3136*zz
      _[2]=zz^2+(723*vv)*xx*ww
      _[3]=yy*zz+(-3425*vv)*xx
      _[4]=xx^2*ww+2956
      _[5]=xx^2*zz+3537*yy
      _[6]=xx^3+(-1299*vv)*yy^2
[2]:
   [1]:
      _[1]=yy*ww+3136*zz
      _[2]=zz^2+(723*vv)*xx*ww
      _[3]=yy*zz+(3425*vv)*xx
      _[4]=xx^2*ww+2956
      _[5]=xx^2*zz-3537*yy
      _[6]=xx^3+(-1299*vv)*yy^2
   [2]:
      _[1]=yy*ww+3136*zz
      _[2]=zz^2+(723*vv)*xx*ww
      _[3]=yy*zz+(3425*vv)*xx
      _[4]=xx^2*ww+2956
      _[5]=xx^2*zz-3537*yy
      _[6]=xx^3+(-1299*vv)*yy^2
> L2;
[1]:
   [1]:
      _[1]=zz^2+(723*vv)*xx*ww
      _[2]=yy^2*ww+(vv)*xx
      _[3]=xx^2*ww+2956
      _[4]=xx^3+(-1299*vv)*yy^2
   [2]:
      _[1]=zz^2+(723*vv)*xx*ww
      _[2]=yy^2*ww+(vv)*xx
      _[3]=xx^2*ww+2956
      _[4]=xx^3+(-1299*vv)*yy^2
> 
. ASSUME(0, testPrimary( L1 , I ) );
> ASSUME(0, testPrimary( L2 , I ) );
> 
. primDecsAreEquivalent(L1, L2);
0

primdecSY( std(I) ); succeeds

[hannes]

fixed with ae8a3a4c90edf6e7b6274f88a45670efb2a36272 by mlee