sympy/sympy — pull request #2070 by sn6uv (2013-05-03 07:29:24+00:00)
Title: add exact values for bessel functions with nu = +-1/2

Implements exact values for Bessel functions of the form `besselX(1/2, z)`, `besselX(-1/2, z)`.

There is one failed test because an exact value is computed instead of a simplification. I'm not sure how best to proceed with this.