Hello, This appears to be a bug in the evaluation of the incomplete Gamma function in the older PARI version(s) used by Sage up to and including 6.3. The computation is correct in the newly released Sage 6.4, which uses the recent stable PARI release 2.7.1.
(See also http://trac.sagemath.org/ticket/17328 for a PARI example showing very different incomplete Gamma function outputs in the two different PARI versions.) Peter Op woensdag 12 november 2014 22:14:29 UTC+1 schreef kcrisman: > > Hmm, I can't reproduce this problem. I am working w/ Maxima 5.34.1. >> >> (%i1) display2d : false $ >> (%i2) foo : 1/log(x)^2 $ >> (%i3) integrate (foo, x, 2, 3); >> (%o3) gamma_incomplete(-1,-log(3))-gamma_incomplete(-1,-log(2)) >> (%i4) %, numer; >> (%o4) 1.273097216447114 >> (%i5) integrate (foo, x); >> (%o5) gamma_incomplete(-1,-log(x)) >> (%i6) ev (%, x=3) - ev (%, x=2); >> (%o6) gamma_incomplete(-1,-log(3))-gamma_incomplete(-1,-log(2)) >> (%i7) %, numer; >> (%o7) 1.273097216447114 >> > > > > >> >> Looks like Maxima handles the definite and indefinite integrals as >> expected. Or perhaps I have misunderstood the problem? >> >> > Nope, you've just confirmed that the way Sage handles incomplete gamma > evaluation is broken somehow. I've opened > http://trac.sagemath.org/ticket/17328 for this. > > > -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To post to this group, send email to sage-support@googlegroups.com. Visit this group at http://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/d/optout.
