Hi, On 11 August 2011 16:24, Aaron Meurer <[email protected]> wrote:
> Indeed, I ran through it with a debugger, and one of the coefficients > was a rational number whose numerator had 3410 digits and denominator > had 3409 digits. And that was just a random number I looked at half > way through the execution; it could get much larger than that even. > So actually, the test does not "hang", it just takes a really long > time. > > By the way, the lex test finishes in a reasonable amount of time. > It's only the grlex test that is slow. And it's only the buchberger > version (f5b is very fast in any case). > > I never realized that Python longs are (apparently) asymptotically > slower than gmpy mpz. > Look at this graph: http://mattpap.github.com/masters-thesis/html/images/ground-factor-large.png. This shows factorization times of (1234*x + 123*y + 12*x + 1)**n. This was done for integers, but in case of rationals (which are used in groebner()) the difference is even bigger. > > Aaron Meurer > > On Thu, Aug 11, 2011 at 7:53 AM, Mateusz Paprocki <[email protected]> > wrote: > > Hi, > > > > On 11 August 2011 15:49, Aaron Meurer <[email protected]> wrote: > >> > >> Skipping the test is a good workaround, but this should be > >> investigated. Python ground types should not be that much slower than > >> gmpy. I suspect there is a bug in PythonIntegerType or > >> PythonRationalType. > > > > Coefficients in this test can have 60 digits and more, so it's quite > > understandable why this test hangs under Python ground types. Skipping is > > fine for now, but really this should be a conditional tests, i.e. do it > if > > gmpy is available and otherwise skip. > > > >> > >> Aaron Meurer > >> > >> On Thu, Aug 11, 2011 at 7:40 AM, Tomo Lazovich < > [email protected]> > >> wrote: > >> > For the record, I am also seeing this hanging in OS X (no gmpy > either). > >> > > >> > On Thu, Aug 11, 2011 at 7:37 AM, Jeremias Yehdegho > >> > <[email protected]> > >> > wrote: > >> >> > >> >> On 08/11/2011 01:55 PM, smichr wrote: > >> >> > groebnertools appears to hang starting with commit > >> >> > >> >> Thank you, fix: https://github.com/sympy/sympy/pull/539 > >> >> > >> >> I think the problem was test_czichowski, which takes too long without > >> >> gmpy (at least on my computer, now that I tried it without gmpy). > >> >> Sorry. > >> >> > >> >> Kind Regards, > >> >> Jeremias > >> >> > >> >> -- > >> >> You received this message because you are subscribed to the Google > >> >> Groups > >> >> "sympy" group. > >> >> 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/sympy?hl=en. > >> >> > >> > > >> > -- > >> > You received this message because you are subscribed to the Google > >> > Groups > >> > "sympy" group. > >> > 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/sympy?hl=en. > >> > > >> > >> -- > >> You received this message because you are subscribed to the Google > Groups > >> "sympy" group. > >> 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/sympy?hl=en. > >> > > > > Mateusz > > > > -- > > You received this message because you are subscribed to the Google Groups > > "sympy" group. > > 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/sympy?hl=en. > > > > -- > You received this message because you are subscribed to the Google Groups > "sympy" group. > 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/sympy?hl=en. > > Mateusz -- You received this message because you are subscribed to the Google Groups "sympy" group. 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/sympy?hl=en.
