文档介绍：10度:
%This program calculate the waveguide by a photonic crystal.
%For two dimension case.
%Only for TM case(Ez,Hx,Hy), in this version试验版本.
clear;
%tic
%Initial parameters and other things.
W=; %Normalized frequency 就是能带图中的纵坐标,单位为(a/lamda)
%The following parameters are control parameters.
WaveGuide=1; %If this program is for Wave Guide? If so, please specify 1.
IsMovie=0; %If you want to play movie, please use 1.
IsFigure=1; %If it will plot the figures? If so, please specify 1.
WantToSeeEp=1; %Do you want to see the distrubution of Ep(TE极化,S极化)? If so, please specify 1.
%End of defining control parameters
MLatx=11; %How many Lattice cell in x
MLaty=11; %How many Lattice cell in y direction.
NMlat=21; %The gird number in each Lattice Cell. 每个栅格中包含的fdtd网格个数
%SHOULD BE ODD INTEGER!!!!奇数整数个
if mod(NMlat,2)==0
NMlat=NMlat+1;
end %Force it to be a odd integer!
NTx=MLatx*NMlat+1; %It is the number of the Grid along x (所以要加1)
NTy=MLaty*NMlat+1; %It is the number of the Grid along y axis.
if WaveGuide==1
Nrow=5; %The row number of coloumns between the PML boundary and the waveguide.(此处定义,现在还不知所措)
end
NPML=12; %How many PML layers will be used in
NTimeSteps=5000; %Total number of Time Steps
Meach=20; %Define the interval for plot figures if IsFigure==1.
%This also works for saving 。

R=; %The radius of dielectric columns,
ea=; %The dielectric constant of these columns.
Zmax=; %The maximum value for z axis when plotting figures.
Colormax=; %The maximum value for colormap when plotting figures.
%Some constants
mu0=4*pi*-7; %Epsilon Zero, if using Gauss Unit, it equals to 1.
e0=*1e-12; %Mu Zero, if using Gauss Unit, it equals to 1.
c=1/sqrt(mu0*e0); %The light speed.
factor=mu0/e0; %The factor between conductivity and permeability.
%Permeability=Conductivity*factor, in

a=1;%e-6; %The lattice 。
W=W*(2*pi*c/a)