This software solves partial differential equations on the two dimensional sphere such as the Jeffery's equation for fiber orientation distributions. The software is described at http://faculty.missouri.edu/~stephen/preprints/pde-sphere.html and pde-sphere-software.pdf.
The version of the software described in the paper is spherical-2.26. The most recent version of the software is spherical-3.13. It is substantially faster than version 2.26, and includes several corrections. (Note versions of spherical-3.xx for xx less than 12 have a serious bug.)
(Version 3.01 comes in a "cuda" version that is capable of using nvidia graphics cards. This only works for the Folgar-Tucker equation, and seems to be unreliable.)
Current versions may be downloaded here. Older versions may be downloaded here.
This work was supported by the National Science Foundation NSF CMMI 0727399.