nob_new.m

在毕业设计中用到的画图的程序 觉得挺有用的

clear all
fid=fopen('datas125.dat','r');
[a,accounta]=fread(fid,29958400,'real*8');
fclose(fid);

%设置区域
n_column=496;
n_row=151;
num=n_column*n_row;
xstart=5;
xend=500;
ystart=150;
yend=450;

fielddensity(1:num)=0;
%镜像
for x=1:num;
    fielddensity(x)=max(a(x:num:accounta-num+x));
end;

field(2*n_row-1,n_column)=0;
for i=1:n_column;
    for j=1:2*n_row-1;
       if j<=n_row
          field(j,i)=fielddensity((i-1)*n_row+j);
       else
            field(j,i)=fielddensity((i-1)*n_row+(n_row*2-j));
        end        
    end;
 end;

x_zero=180;
y_zero=300;
cell_cm=0.05;
field_max=max(max(field));
cell_wavelength=1/60;
mirror=120;




x1=-80/60:1/60:80/60;
x2=(mirror+10):1:(xend-x_zero);
x3=(xstart-x_zero):1:(xend-x_zero);
%x2_l=(300-x_zero)/60:1/60:(400-x_zero)/60;

%
field_x1=field(n_row,x_zero+mirror+1+10-xstart:xend+1-xstart);
%x_3db=order_find3dB(field_x,1/60);
x_max=max(field_x1);
x_max_ind=find(field_x1==x_max)+9;
field_x1=field_x1/x_max;
%field_x1=field_x(1:x_max_ind);
%field_x2=field_x(x_max_ind+1:156);%x_3db1=find(field_x1>=0.707,1);
%x_3db1=x_3db1-x_max_ind;
%x_3db2=find(field_x2<=0.707,1);



z_max=max(field(1:n_row*2-1,x_zero+mirror+1+x_max_ind-xstart));
field_z=field(71:231,x_zero+mirror+1+x_max_ind-xstart)/z_max;
%field_z11=field(71:151,244+x_max_ind-xstart)/z_max;
%field_z12=field(152:231,244+x_max_ind-xstart)/z_max;
%z_3db1=find(field_z11>=0.707,1);
%z_3db1=z_3db1-81;
%z_3db2=find(field_z12<=0.707,1);
%z_3db=(z_3db2-z_3db1);


% distribution of the whole field
x=(49+xstart-x_zero)/60:1/60:(400+xstart-x_zero)/60;%
y=(ystart-y_zero+100)/60:1/60:(yend-y_zero-100)/60;
figure1=figure();
imagesc(x,y,field(100:201,50:401)/field_max)
xlabel('x-axis(λ)');
ylabel('y-axis(λ)');
title('总体场强分布图');

figure2=figure();
plot(x1,field_z);
xlabel('x-axis(λ)');
ylabel('y-axis(intensity)');
title('焦点处横向场强分布');
figure3=figure();
plot(x2,field_x1)
xlabel('x-axis(λ)');
ylabel('y-axis(intensity)');
title('焦点处纵向场强分布');
figure4=figure();
plot(x3,field(n_row,1:n_column)/field_max)
xlabel('x-axis(λ)');
ylabel('y-axis(intensity)');
title('横向场强分布');
%figure5=figure();
%plot(x2,field(151,240-xstart:400-xstart)/field_max/(max(field(151,240-xstart:400-xstart)/field_max)))
%xlabel('x-axis(λ)');
%figure6=figure();
%plot(x1,field(1:301,270-xstart)/field_max/(max(field(1:301,270-xstart)/field_max)))
%xlabel('x-axis(λ)');
%ylabel('y-axis(intensity)');
%title('焦点处纵向场强分布');
%imagesc(x,y,field/field_max)
field_x(1:141)=0;
field_x=field_x1(1:141);