Hi!
It seems to me, that restricted to rings and ideals,
the ordering looks like
2 5
-1 -2
So, the Matrix M(1,1,0,-1) is probably useless in this example.
Michael
Am 09.09.2009 um 12:56 schrieb Martin Albrecht:
>
> Hi there,
>
> I have to say that I don't like the
>
> WeightVector(2,5) + ModuleOrder('c')
>
> syntax. WeightVector is a modification of the following term order (in
> Singular). It feels much more natural to me to simply do:
>
> TermOrder('lex',weights=(2,5))
>
> Also, I don't really understand what
>
>> ring R =0,(x, y), (a(2,5), c, a(-1,-2), M(1,1,0,-1)); R;
> // characteristic : 0
> // number of vars : 2
> // block 1 : ordering a
> // : names x y
> // : weights 2 5
> // block 2 : ordering c
> // block 3 : ordering a
> // : names x y
> // : weights -1 -2
> // block 4 : ordering M
> // : names x y
> // : weights 1 1
> // : weights 0 -1
>> deg(x); // note that the 1st "a"/"M"/weighted ordering is used for
>> "deg"
> 2
>> deg(y);
> 5
>
> does exactly. As far as I can see a(X,Y) modifies the following
> ordering which
> eventually is the Matrix odering (1,1,0,-1). What's the role of the
> second
> a(X,Y) in the example above?
>
> Cheers,
> Martin
>
>
> --
> name: Martin Albrecht
> _pgp: http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x8EF0DC99
> _otr: 47F43D1A 5D68C36F 468BAEBA 640E8856 D7951CCF
> _www: http://www.informatik.uni-bremen.de/~malb
> _jab: [email protected]
>
>
>
>
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