# Singular

 Page 1 of 1 [ 5 posts ]
 Print view | E-mail friend Previous topic | Next topic
Author Message
 Post subject: Debug mode for inbuilt "reduce" functionPosted: Thu Nov 20, 2014 12:37 am
Is there any option to print each step of "reduce" function.?

Top

 Post subject: Re: Debug mode for inbuilt "reduce" functionPosted: Thu Nov 20, 2014 12:11 pm

Joined: Wed May 25, 2005 4:16 pm
Posts: 236
Have a look at NFMora in teachstd.lib and set printlevel to 1 (or higher):
Code:
>LIB "teachstd.lib";
> printlevel=1;
>    ring r=0,(x,y,z),dp;
>    poly f = x2y2z2+x5+yx3+z6-3y3;
>    ideal G = x2y+x2,y3+xyz,xyz2+z6;
>    NFMora(f,G);"";

// Input for NFMora is (f,T):
// f:
x2y2z2+z6+x5+x3y-3y3
// T:
T[1]=x2y+x2
T[2]=y3+xyz
T[3]=z6+xyz2
// Reduce f with T, eventually enlarging T for local ordering

//                Reduction-step in NFMora: 0
// h = (f after 0 reductions) reduction with g from T:
// g = element of minimal ecart in T s.t. LM(g)|LM(h):
// h:
x2y2z2+z6+x5+x3y-3y3
// g:
x2y+x2
// T-set enlarged for next reduction? (yes/no = 1/0):   0

//                Reduction-step in NFMora: 1
// h = (f after 1 reductions) reduction with g from T:
// g = element of minimal ecart in T s.t. LM(g)|LM(h):
// h:
z6+x5-x2yz2+x3y-3y3
// g:
z6+xyz2
// T-set enlarged for next reduction? (yes/no = 1/0):   0

// normal form is:
x5-x2yz2+x3y-xyz2-3y3

Top

 Post subject: Re: Debug mode for inbuilt "reduce" functionPosted: Fri Nov 21, 2014 12:05 am
NFMora function works only for the fields. We are working on integer rings. Is there any function to reduce in integer rings ?

Top

 Post subject: Re: Debug mode for inbuilt "reduce" functionPosted: Fri Nov 21, 2014 12:05 pm
Bavithra wrote:
NFMora function works only for the fields. We are working on integer rings. Is there any function to reduce in integer rings ?

To my knowledge there is no educational implementation over integer rings in Singular.

I'm aware of the following educational alternative:
sagemath.org/doc/reference/polynomial_rings/sage/rings/polynomial/toy_buchberger.html
However, there is no guarantee that this implementation is not buggy, too ( I didn't check )

Top

 Post subject: Re: Debug mode for inbuilt "reduce" functionPosted: Mon Nov 24, 2014 3:52 pm
Did I screw up my last post ?

I thought that in my last post I also wrote that the computation in polynomial rings over integers
(std(), reduce(), intersect() and others ) in Singular is broken (for years and probably did never work):
for some (not for all ) input the user may and will get incorrect results.

However, there is ongoing work to fix this issue.

bughunter wrote:
Bavithra wrote:
NFMora function works only for the fields. We are working on integer rings. Is there any function to reduce in integer rings ?

To my knowledge there is no educational implementation over integer rings in Singular.

I'm aware of the following educational alternative:
sagemath.org/doc/reference/polynomial_rings/sage/rings/polynomial/toy_buchberger.html
However, there is no guarantee that this implementation is not buggy, too ( I didn't check )

Top

 Display posts from previous: All posts1 day7 days2 weeks1 month3 months6 months1 year Sort by AuthorPost timeSubject AscendingDescending
 Page 1 of 1 [ 5 posts ]

 You can post new topics in this forumYou can reply to topics in this forumYou cannot edit your posts in this forumYou cannot delete your posts in this forumYou cannot post attachments in this forum

 It is currently Wed Apr 08, 2020 10:32 pm