clear all

load y1.txt
%load y2.txt
%load y3.txt

y1=flipud(y1);
%y2=flipud(y2);
%y3=flipud(y3);

YY1=-y1(1:1000,2);                 %y1的第二列
%YY2=-y2(1:1000,2);
%YY3=-y3(1:1000,2);

T=0.1;
for k=1:1000
   X(k)=k*T;
end   

for i=1:1000
   jx(i)=0.0;
end

plot(jx,'r')                       %縱坐標(biāo)都為0的曲線(一條水平紅線)
hold on                            %hold on 用于保留當(dāng)前圖形和當(dāng)前坐標(biāo)軸屬性，后面的圖形命令只能在當(dāng)前存在的坐標(biāo)軸中增加圖形，即設(shè)置當(dāng)前坐標(biāo)軸屬性NexPlot為add
plot(YY1,'k')                      %按YY1的序號(hào)用黑線畫出YY1

%YY3=jxtiqu(YY3,X);
%YY2=jxtiqu(YY2,X);
YY1=jxtiqu(YY1,X);

%plot(YY3,'r')
%plot(YY2,'b')
plot(YY1,'g')