Program	:	xyfdtd - 2 dimensional Finite-Difference Time Domain demo
			 program using the Yee algorithm and Mur absorbing
			 boundary conditions. Uses X-windows to display the
			 wave propogation. The input file contains all the
			 input parameter definitions with a sample case.

Author	:	Louis Wilson - Main computational engine
		Jeff Sheffel - X-windows Graphic Interface

e-mail	:	lwilson@netcom.com

Libraries used -
		libX11.a, libm.a

Comments -
		When originally written, this was called xfdtd.  Since
		then, xfdtd has been trademarked by Remcom, Inc., so the
		name has been changed to xyfdtd.  However, the code itself
		is the same as when it was called xfdtd.

		Compiled on a Sun Sparcstation 1 using Sun Fortran V1.2

		Compile with -
			cc -c vix2d-f77.c
			f77 -o xyfdtd XYfdtd.f viz2d-f77.o -lX11 -lm

		Sun fortran allows mixing of Fortran and C routines, if your
		compiler does not, you may be able to use the Fortran-to-C
		converter from netlib (f2c at research.att.com).

		The /misc directory contains routines for writing ascii or 8-bit
		files for plotting plotting. If you are not running X-windows
		simply comment out the display routine call and dump the time
		step of interest to a file.

References:
		1. K. S. Yee, "Numerical solution of initial boundary value
		   problems involving Maxwell's equations in isotropic media,"
		   IEEE Trans. Antennas Propogat., vol. AP-14, pp. 302-307,
		   May 1966.

		2. G. Mur, "Absorbing boundary conditions for the finite-
		   difference approximation of time-domain electromagnetic
		   field equations," IEEE Trans. Electromagn. Compat.
		   vol EMC-23, pp. 377-382, Nov. 1981.

Remarks	:

		Comments and bug reports welcome.