The Multipole thorn performs spherical harmonic mode decomposition of Cactus grid functions on coordinate spheres. It can decompose multiple grid functions with any spin-weight on multiple spheres. This thorn uses the interpolator interface to access grid functions, so works with mesh-refinement and multi-patch.

• An interpolator

• WeylScal4 can be used to compute the Weyl scalars, which can then be decomposed into modes on coordinate spheres by Multipole.

Multipole has been used in the following publications:

This thorn is copyright (C) 2007-2011 (C) by Ian Hinder and Andrew Knapp.

This thorn is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This thorn is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this thorn (see the file COPYING in this directory); if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA