中文说明：％ 本程序实现2维TM波FDTD仿真％ 此程序用PML设置吸收边界条件％ FDTD_2D_kongqi_PML％ 仅喊有Ez，Hx，Hy分量
English Description：
%This program realizes 2-D TM wave FDTD simulation. This program uses PML to set absorption boundary condition% FDTD_ 2D_ kongqi_ PML% only has EZ, HX, hy components