Yes, this is not yet implemented in Singular yet. Although GTZ algorithm gives error whereas SY algorithm clearly mentions "Not implemented".
If you are interested in char 0, and not specifically Complex, then using QQ instead of CC gives a workaround. As far as your example is concerned, it may not make any difference and Singular can do the computations. However, Singular documentation (and also the libraries) mention that the algorithm works in Char 0. So the possible interpretation for this line could be as follows:(Need to verify with SIngular team) The algorithm works if charstr(basering) = "0". (Note that to define a ring in Singular is "ring R = charstr, varstr, ordstr.") Hope this helps. VInay On 4 April 2012 09:30, Dima Pasechnik <[email protected]> wrote: > > > On Wednesday, 4 April 2012 10:28:42 UTC+8, vasu wrote: >> >> Hi >> I am trying to run the following piece of code on sage >> >> >> R.<x,y,z> = CC['x,y,z'] >> I = (x-(y*z), y-(x*z), x*y)*R; I >> >> I.primary_decomposition() >> >> and I seem to be getting the following error: >> >> Traceback (most recent call last): >> File "<stdin>", line 1, in <module> >> File "_sage_input_9.py", line 10, in <module> >> exec compile(u'open("___code___.py"**,"w").write("# -*- coding: utf-8 >> -*-\\n" + >> _support_.preparse_worksheet_**cell(base64.b64decode("**SS5wcmltYXJ5X2RlY29tcG9zaXRpb2**4oKQ=="),globals())+"\\n"); >> execfile(os.path.abspath("___**code___.py")) >> File "", line 1, in <module> >> >> File "/tmp/tmpn0I8Lz/___code___.py"**, line 2, in <module> >> exec compile(u'I.primary_**decomposition() >> File "", line 1, in <module> >> >> File >> "/home/heidar/Desktop/sage/**sage-4.8-linux-32bit-ubuntu_**10.04_lts-i686-Linux/local/**lib/python2.6/site-packages/**sage/rings/polynomial/multi_**polynomial_ideal.py", >> line 601, in __call__ >> return self.f(self._instance, *args, **kwds) >> File >> "/home/heidar/Desktop/sage/**sage-4.8-linux-32bit-ubuntu_**10.04_lts-i686-Linux/local/**lib/python2.6/site-packages/**sage/rings/polynomial/multi_**polynomial_ideal.py", >> line 1012, in primary_decomposition >> return [I for I, _ in self.complete_primary_**decomposition(algorithm)] >> File >> "/home/heidar/Desktop/sage/**sage-4.8-linux-32bit-ubuntu_**10.04_lts-i686-Linux/local/**lib/python2.6/site-packages/**sage/rings/polynomial/multi_**polynomial_ideal.py", >> line 601, in __call__ >> return self.f(self._instance, *args, **kwds) >> File >> "/home/heidar/Desktop/sage/**sage-4.8-linux-32bit-ubuntu_**10.04_lts-i686-Linux/local/**lib/python2.6/site-packages/**sage/rings/polynomial/multi_**polynomial_ideal.py", >> line 502, in wrapper >> return func(*args, **kwds) >> File >> "/home/heidar/Desktop/sage/**sage-4.8-linux-32bit-ubuntu_**10.04_lts-i686-Linux/local/**lib/python2.6/site-packages/**sage/rings/polynomial/multi_**polynomial_ideal.py", >> line 940, in complete_primary_decomposition >> P = primdecSY(self) >> File "function.pyx", line 1035, in >> sage.libs.singular.function.**SingularFunction.__call__ >> (sage/libs/singular/function.**cpp:10114) >> TypeError: Cannot call Singular function 'primdecSY' with ring parameter of >> type '<class >> 'sage.rings.polynomial.multi_**polynomial_ring.**MPolynomialRing_polydict_**domain'>' >> >> >> >> When I use field QQ instead of CC, things are fine. So I'd be glad if >> somebody can point out what the issue is? >> > > this is a limitation of Singular, AFAIK. > >> >> Thanks >> Vasu >> > -- > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected] > For more options, visit this group at > http://groups.google.com/group/sage-support > URL: http://www.sagemath.org > -- To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
