Back to Forum | View unanswered posts | View active topics
|
Page 1 of 1
|
[ 3 posts ] |
|
Author |
Message |
gema
|
Post subject: question-multiplicative subsets Posted: Thu Oct 23, 2008 11:37 am |
|
Joined: Thu Oct 23, 2008 11:16 am Posts: 2
|
Hello everybody,
I would like to know if given a zero dimensional ideal J in Q[x1,...,xn] and a multiplicative subset S of Q[x1,...,xn] , it is possible to define in SINGULAR S-1(Q[x1,...,xn]/J).
And given g in Q[x1,...,xn] , is it possible to define in SINGULAR the saturation of J with respect to g?
thanks in advance for your help, best wishes, gema m.
|
|
Top |
|
|
greuel
|
Post subject: Posted: Sat Nov 15, 2008 2:57 am |
|
Joined: Mon Aug 29, 2005 9:22 am Posts: 41 Location: Kaiserslautern, Germany
|
Hi, You can localize in the maximal ideal <x1,...,xn> just by defining a local ring (local ordering, ends with an s = referring to series) eg. ring r = 0,x(1..n),ds; Localization in any other maximal ideal <x1-p1,...,xn-pn> is possible by translation of p to 0 (apply the translation to your ideal) and then as above. Localizations w.r.t. arbitrary mlutiplicative sets are not possible.
If you wish to analyse a 0-dim ideal you should try a primary decomposition first.
sat(J,g); does the saturation.
Here is an example:
ring r = 0,(x,y,z),dp; poly g = x3+y5+z2 +xyz; ideal J = jacob(g); LIB"primdec.lib"; primdecGTZ(J); /* [1]: [1]: _[1]=z2 _[2]=y3z _[3]=30y4+y2z _[4]=-y2z+6xz _[5]=xy+2z _[6]=3x2+yz [2]: _[1]=z _[2]=y _[3]=x [2]: [1]: _[1]=z+3888000 _[2]=y-360 _[3]=x-21600 [2]: _[1]=z+3888000 _[2]=y-360 _[3]=x-21600 */ sat(J,g); /* [1]: _[1]=z+3888000 _[2]=y-360 _[3]=x-21600 [2]: 1 */
|
|
Top |
|
|
gema
|
Post subject: thanks -multiplicative subsets Posted: Sat Nov 15, 2008 11:22 am |
|
Joined: Thu Oct 23, 2008 11:16 am Posts: 2
|
thanks a lot for your answer,
kind regards, gema m.
|
|
Top |
|
|
|
Page 1 of 1
|
[ 3 posts ] |
|
|
You can post new topics in this forum You can reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot post attachments in this forum
|
|
It is currently Fri May 13, 2022 11:05 am
|
|