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jakobkroeker / test_singular

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std(J)<>std(std(J)) over integers with options 'redSB' and 'redTail' #103

Open jakobkroeker opened 9 years ago

jakobkroeker commented 9 years ago

origin: https://github.com/surface-smoothers/lipmanresolve/issues/380

LIB("wrappers.lib");

ring rng = integer,(x,y,z),lp;
option(redSB);
option(redTail);

ideal I = 
-98xyz2+82xy-29y2z+53,
-32xy2+11xy+56y2+135;
ideal J = 
-93x2y2z-108y2+79,
-20x4y+81xy2z+72xz,
-41xyz2;

ideal gJ = groebner(J);
ideal ggJ = groebner(gJ);
gJ;
ggJ;
 ASSUME(0, gJ[15]==ggJ[15] );

 ASSUME(0, idealRepresentationsEqual(gJ,ggJ ));

despite of the options redSB and redTail
gJ[15] is not equal to ggJ[15].

ok or not?

jakobkroeker commented 9 years ago

seems ok now

jakobkroeker commented 8 years ago

bugfix was merged

jakobkroeker commented 8 years ago 
LIB("wrappers.lib");

ring rng = integer,(x,y,z),lp;
option(redSB);
option(redTail);

ideal I = 
-98xyz2+82xy-29y2z+53,
-32xy2+11xy+56y2+135;
ideal J = 
-93x2y2z-108y2+79,
-20x4y+81xy2z+72xz,
-41xyz2;

ideal gJ = groebner(J);
ideal ggJ = groebner(gJ);
gJ;
ggJ;
 ASSUME(0, gJ[15]==ggJ[15] );

 ASSUME(0, idealRepresentationsEqual(gJ,ggJ ));

now the issue is at position 10

simplified example :

ring rng = integer,(x,y),lp;
ideal J = -x2y-y, -x4+xy ;

ideal gJ = groebner(J);
ideal ggJ = groebner(gJ);
gJ;
ggJ;

ASSUME(0, idealRepresentationsEqual(gJ,ggJ ));

output

> ideal J = -x2y-y, -x4+xy ;
> 
. ideal gJ = groebner(J);
> ideal ggJ = groebner(gJ);
> gJ;
gJ[1]=y3+y
gJ[2]=xy+y2
gJ[3]=x4-xy
> ggJ;
ggJ[1]=y3+y
ggJ[2]=xy+y2
ggJ[3]=x4+y2
> 
. ASSUME(0, idealRepresentationsEqual(gJ,ggJ ));
// I[3 ]<>J[3]
   ? ASSUME failed:ASSUME(0, idealRepresentationsEqual(gJ,ggJ ));
   ? error occurred in or before STDIN line 1652: `           return( int(0) );`
   ? wrong type declaration. type 'help int;'
>

well, the representation is not equal, but why it is an issue?