Hi Eliot, On Thu, 18 Feb 2010 04:02:16 -0800 (PST) eliot brenner <eliotpbren...@gmail.com> wrote:
> Thanks! > > In the meantime, any suggestions for a work-around (besides write the > entire program in PARI or C)? You can just use mpmath to compute besselk. The ticket Dan mentioned (#3426) has these examples: sage: from mpmath import * sage: mp.dps = 25; mp.pretty = True sage: besselk(0, -1) (0.4210244382407083333356274 - 3.97746326050642263725661j) sage: besselk(-1*I - 1, 0) +inf sage: besselk(-1, -1) (-0.60190723019723457473754 - 1.775499689212180946878577j) sage: besselk(0, -1-I) (-1.479697108749625193260947 + 2.588306443392007370808151j) BTW, does anyone think we need to open a ticket for the error in converting back from pari. This (From Eliot's previous message) sounds serious: > Apparently, SAGE is interpreting very small floating point numbers as > very large ones, "wrapping around" the exponents. What I would like to > do is (obviously) have SAGE report the real answer, or failing that, > have it instead judge a very small floating point number to be 0 and > return 0 as the answer instead of a very large floating point. Cheers, Burcin -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
