how to put a function inside animation
显示 更早的评论
Hi, I have to program a bouncing ball using a function I created before called drawball, now I can't implement this function inside my program, it only shows me a big ball, here are the scripts I used:
function drawdisc(x0,y0,r,c)
t=0:0.01:2*pi;
x=r*cos(t)+x0;
y=r*sin(t)+y0;
fill(x,y,c)
end
the bouncing ball script:
clc;
initpos=0; %Ball's initial vertical position
initvel=20; %Ball's initial vertical velocity
r_ball=1; %Ball's radius
gravity=10; %Gravity's acceleration
c_bounce=0.85; %Bouncing's coefficient of elasticity
dt=0.0125; %Animation timestep;
pos=r_ball; %Ball's current vertical position
vel=initvel;%Ball's current vertical velocity
axis([0 20 0 25])
while 1
pos=pos+(vel*dt); %Ball's current vertical position
vel=vel-(gravity*dt); %Ball's current vertical velocity
if pos<0
vel=-vel*c_bounce; %Balls' current vertical velocity
end
drawball(1,pos,1,'b')
pause(0.01)
end
your help is appreciated!!
采纳的回答
Walter Roberson
2017-1-7
0 个投票
You define a function named "drawdisc" but you call upon "drawball" in your code.
You call upon drawball(1,pos,1,'b') in your code. It would make more sense to call upon drawball(1,pos,r_ball,'b')
If you the Image Processing Toolbox and a newer MATLAB you might want to consider using viscircles() instead of your own routine. You might also want to consider using scatter() with a marker size and with 'filled'. Or you might want to use plot() with 'o' as the marker and with a MarkerSize and MarkerFaceColor argument.
2 个评论
Meriem Boukhaima
2017-1-7
Walter Roberson
2017-1-7
You need to either "hold on" or set the axes xlim and ylim (which automatically sets xlimmode and ylimmode to manual). Make sure you do that after each time you draw the ball. (Better yet would be for your drawing routine to detect that the ball had already been drawn and to update its position instead of creating a new drawing, but even that requires that you had set xlim and ylim)
更多回答（0 个）
类别
在 帮助中心 和 File Exchange 中查找有关 Animation 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
Translated by 
