This directory contains some poly-dimensional, polymorphic difference
equations solvers. Better documentation will appear later. The
boundary remains a problem. "Inner" solutions leave the array boundary
fixed, and only update the inside. Outer solutions will add default
values to the boundary, so that the result of stencilling will produce
an array of the same size. 

The ideas are iluustrated using the Conway's Game of Life in life.fsh.
Some trivial games are supplied in comments at the end of the file.
average.fsh shows how to relax an array so that each entry is the
average of its neighbours.