Cactus Code Thorn WaveToy2DF77
Author(s)    : Gabrielle Allen
Maintainer(s): Cactus team
Licence      : LGPL
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1. Purpose

This thorn illustrates the solution of the scalar wave equation in 2D using
centered explicit finite differencing. Included are routines to
NOTE: This thorn isn't working properly yet for multiple processors, it 
      will be fixed very soon in the development version.

 * Set up and register the 2D spatial coordinate system
 * Calculate initial data
 * Evolve using a standard explicit method

The Cactus infrastructure used includes

 * Boundary conditions  (CactusBase/Boundary)
 * Timestep calculation (CactusBase/Time)
 * Parallel driver      (CactusPUGH/PUGH)
 * IO			(Standard IO thorns)