各位指点下

chenhan

%弹性蹦球演示程序
figure(1);%定义函数
axis([-5.1,5,-0.05,1.05]);%绘制二维图形
hold on;%保持当前图形及轴系所有的特性
axis('off');%覆盖坐标刻度，并填充背景
%通过填充绘出台阶及两边的挡板
fill([4.12,4.22,4.22,4.12],[-0.05,-0.05,1.05,1.05],'y');
fill([-5,-3.2,-3.2,-5],[-0.05,-0.05,0,0],'g');
fill([-3.2,-2.8,-2.8,-3.2],[-0.05,-0.05,0.2,0.2],'g');
fill([-3.2,-1.4,-1.4,-3.2],[0.2,0.2,0.25,0.25],'g');
fill([-1.4,-1,-1,-1.4],[0.2,0.2,0.45,0.45],'g');
fill([-1.4,0.4,0.4,-1.4],[0.45,0.45,0.5,0.5],'g');
fill([0.4,0.8,0.8,0.4],[0.45,0.45,0.7,0.7],'g');
fill([0.4,2.0,2.0,0.4],[0.7,0.7,0.75,0.75],'g');
fill([2.0,2.3,2.3,2.0],[-0.05,-0.05,0.75,0.75],'g');
fill([2.3,4.12,4.12,2.3],[-0.05,-0.05,0,0],'g');
%x2=line([-5,5],[0.25,0.25],'color','g','linestyle','-', 'markersize',50)%设置台阶边框线，颜色，擦试方式
%line([-5,5],[0.5,0.5],'color','b','linestyle','-', 'markersize',50)%设置球与地面接触面的颜色，擦试方式
%line([-5,5],[0.75,0.75],'color','b','linestyle','-', 'markersize',50)%设置球与地面接触面的颜色，擦试方式
head=line(-5,1,'color','r','linestyle','.','erasemode','xor', 'markersize',60);%设置小球颜色，大小，线条和擦试方式
%body=line(-5,1,'color','b','linestyle','-','erasemode','none'); %描绘轨迹线
%设置初始条件
while 1
t=4;
dt=0.001;
w=0;
dw=0.001;
w=0;%设置球弹起的初始位置
%设置球弹起的高度
while t<=4.12
    t=dt+t;
if w<=1
    w=dw+w;
else
    w=-1;
end
y=(-w*w)+1;
set(head,'xdata',t,'ydata',y);%设置球的运动
%set(body,'xdata',t,'ydata',y);%描绘轨迹线
drawnow;
end %结束程序
w=0;%设置球弹起的初始位置
%设置球弹起的高度
while t>=2.11
    t=t-dt;
if w<=1
    w=dw+w;
else
    w=-1;
end
y=(-w*w)+1;
set(head,'xdata',t,'ydata',y);%设置球的运动
%set(body,'xdata',t,'ydata',y);%描绘轨迹线
drawnow;
end %结束程序
w=0;%设置球弹起的初始位置
  %设置球弹起的高度
while t>=1.11
    t=t-dt;
if w<=1
    w=dw+w;
else
    w=-1;
end
y=(-w*w)/4+1;
set(head,'xdata',t,'ydata',y);%设置球的运动
%set(body,'xdata',t,'ydata',y);%描绘轨迹线
drawnow;
end %结束程序
w=-0.71;%设置球弹起的初始位置
  %设置球弹起的高度
while t>=-0.62
    t=t-dt;
if w<=1
    w=dw+w;
else
    w=-1;
end
y=(-w*w)/2+1;
set(head,'xdata',t,'ydata',y);%设置球的运动
%set(body,'xdata',t,'ydata',y);%描绘轨迹线
drawnow;
end %结束程序
w=-0.71;%设置球弹起的初始位置
  %设置球弹起的高度
while t>=-2.31
    t=t-dt;
if w<=1
    w=dw+w;
else
    w=-1;
end
y=(-w*w)/2+0.75;
set(head,'xdata',t,'ydata',y);%设置球的运动
%set(body,'xdata',t,'ydata',y);%描绘轨迹线
drawnow;
end %结束程序
w=-0.71;%设置球弹起的初始位置
  %设置球弹起的高度
while t>=-4
    t=t-dt;
if w<=1
    w=dw+w;
else
    w=-1;
end
y=(-w*w)/2+0.5;
set(head,'xdata',t,'ydata',y);%设置球的运动
%set(body,'xdata',t,'ydata',y);%描绘轨迹线
drawnow;
end %结束程序
for i=0:0.01:200%设置延时
    y=i+2;
    if(y>199)
    end
end
end