MATLAB: How to put a function inside animation

animation

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!!

Best Answer

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.
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