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Topic review - On computation of monodromy structure
Author Message
  Post subject:  Re: On computation of monodromy structure  Reply with quote
Finally the preprint is: arXiv:0907.5252

We acknowledge the power of Singular and Singular.Forum
Post Posted: Thu Jul 30, 2009 6:01 am
  Post subject:  Re: On computation of monodromy structure  Reply with quote
Thank you very much, this was very important for me!
Of course you can use this example for any purpose!


(We were particularly interested in this example as it seems to be a counterexample to some old question. Hopefully a short note will be posted to the arXiv next week.)
Post Posted: Sat Jul 25, 2009 3:02 pm
  Post subject:  Re: On computation of monodromy structure  Reply with quote
Hi Dmitry,

this example is tough (and interesting!) indeed. It took nearly 30 hours on a quite decent compute server and here's the data, which 'monodromy(f);' returns:
[1]:
_[1]=-1/4
_[2]=0
_[3]=1/9
_[4]=1/5
_[5]=2/9
_[6]=1/4
_[7]=1/3
_[8]=2/5
_[9]=4/9
_[10]=1/2
_[11]=5/9
_[12]=3/5
_[13]=2/3
_[14]=7/9
_[15]=4/5
_[16]=8/9
[2]:
1,2,1,1,1,1,1,1,1,1,1,1,1,1,1,1
[3]:
1,3,3,3,3,1,3,3,3,1,3,3,3,3,3,3

Why are you interested in this curve? Does it bear a special name? May I use it as benchmark for our collection?

With best regards,
Viktor Levandovskyy
Post Posted: Sun Jul 19, 2009 4:08 pm
  Post subject:  On computation of monodromy structure  Reply with quote
I'm trying to compute the monodromy in a specific example.
the simplest script:

LIB "gmssing.lib";
ring r = 0,(x,y,z),ds;
poly f=x*y*z*(x+y+z)+z^4*x+y^4*z+x^4*y;
monodromy(f);

(I need the Jordan block structure, not just the eigenvalues, hence I can't use e.g. spectrum(f) ).

Unfortunately my laptop is very slow (and not enough memory).

*Are there any ways to improve smth for this particular example?
*Or maybe somebody can just run this on a faster computer and put the results here?
Post Posted: Mon Jun 29, 2009 1:53 pm


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