Received from Pauli Virtanen on Fri, Dec 21, 2012 at 08:59:02AM EST:
Dag Sverre Seljebotn <d.s.seljebotn <at> astro.uio.no> writes: [clip]
Do you have an implemention of the Bessel functions that work as you wish in C or Fortran? If so, that could be wrapped and called from Python.
For spherical Bessel functions it's possible to also use the relation to Bessel functions, which have a better implementation (AMOS) in Scipy:
import numpy as np from scipy.special import jv
def sph_jn(n, z): return jv(n + 0.5, z) * np.sqrt(np.pi / (2 * z))
print sph_jn(536, 2513.2741228718346 + 201.0619298974676j) # (2.5167666386507171e+81+3.3576357192536334e+81j)
This should solve the problem.
You can also try the spherical Bessel function in Sympy; it should be able to handle this case as well [1]. L.G. [1] http://docs.sympy.org/0.7.2/modules/functions/special.html#bessel-type-funct...