To get back to the question of argument order, it seems strange to me that pari(2).besselk(3) should meant K_2(3) rather than K_3(2).
sage: pari(2).besselk(3) 0.06151045847174203765682007145 sage: bessel_K(2,3) 0.0615104584717420 bessel_K(nu,x) is written K_nu(x) because the first argument nu is in some sense a parameter - in many cases an integer - identifying K_nu as the nu'th Bessel function of type K. So I would naively imagine that pari(2).besselk(3) would mean `take the 3rd bessel function and apply it to 2'. Is there some general philosophy that dictates the opposite behavior? Like, say, "f(x,y) always translates to x.f(y)"? As a preview of an issue I'll raise in a separate post, note that Sage is not giving us its best with bessel_K: sage: bessel_K(2+I,3+I) Traceback (most recent call last): ... TypeError: Unable to convert x (='0.043192827269587267-0.040059538066532876*I') to real number. The answer here is correct, and the only problem is that Sage was expecting the result to be a real number. Cheers, Peter --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://sage.math.washington.edu/sage/ and http://sage.scipy.org/sage/ -~----------~----~----~----~------~----~------~--~---