Error using matlab.gra​phics.char​t.primitiv​e.Line/set Invalid or deleted object.

How do i deal with this problem? Attached below is a function that is supposed to "animate" and the script below that calls the function. Thanks.

%Function saved as AD_Crane
function crane(t,x)

w=0.75; %width of mass 
h=0.75; %height of mass
l_r=0.75; %length of rod
w_r=0.1; %width of rod
x_mass = [-w/2,-w/2,w/2,w/2,-w/2]; %x coordinates of block
y_mass = [0,h,h,0,0]; %y coordinates of block
x_rod = [-w_r/2,-w_r/2,w_r/2,w_r/2,-w_r/2]; %x coordinates of rod
y_rod = [-l_r,0.1,0.1,-l_r,-l_r]; %y coordinates of rod
Hf=figure('Units','normalized','Position',[.1,.1,.8,.8]); %sets position of plot on screen
Ha_f2a1=subplot(2,1,1); %sets size of plot
Hls_f2plot1=plot(0,0);
axis([0,t(end),-2,2]);
grid on;
xlabel('t (sec)');
ylabel('x (m)') ;

Hp_f2mass=fill(x_mass+x(1),y_mass,'b');
axis([-2,2,-2,2]);
grid on;
Hl_m=line(x(1),h/2,'Marker','O','MarkerSize',8,'MarkerFaceColor','k'); %places dot at center of block
drawnow;
tic;
while toc<1
end;
tic;
for n=1:length(t)
   %L=L0+x(n)-W/2;   
  
   set(Hls_f2plot1,'XDATA',t(1:n),'YDATA',x(1:n)); %attempts to plot as it cycles through values of t and x
   set(Hp_f2mass,'YDATA',x_mass+x(n));
   %set(Hl_cm,'XData',x(n));
   %set(Hgt_springdamp,'Matrix',[L,0,0,-L0;0,1,0,H/2;0,0,1,0;0,0,0,1]);
   
   drawnow;   
end

%Script that calls above function
y0=[1 0 0 0];
tspan=[0:0.1:30];
[t,y]=ode45(@myodefun,tspan,y0,[]);
AD_Crane(t,y(:,3));
%plot(t,y)

function ydot= myodefun(t,y)
ydot(1,1)=y(2);
ydot(2,1)=(2.4*y(2)^2*sin(y(1)) + 9.81*sin(y(1))*cos(y(1)) + 0.125*(y(2)^2)*sin(y(1))*(cos(y(1))^2))/(0.5*cos(y(1)) + 0.25*cos(y(1))^2 -5.3);
ydot(3,1) = y(4);
ydot(4,1) = (-1.2625*y(2)^2*sin(y(1)) - 2.4525*sin(y(1))*cos(y(1)))/(-5.3 + 0.25*cos(y(1))^2);
end

Answer 1

[Cris LaPierre]

First, your function name and file name should be the same. I'd update funciton declaration to be AD_Crane(t,x)

%Function saved as AD_Crane
function crane(t,x)

Now, the issue is you replace the Hls_f2plot1 with the Hp_f2mass plot. So in your for loop at the end when you try to set properties of Hls_f2plot1, it no longer exists and you get the error. I suspect that you just forgot to assign Hp_f2mass_plot to subplot(2,1,2). Do that, and the error goes away.

Ha_f2a1=subplot(2,1,1); %sets size of plot
Hls_f2plot1=plot(0,0);
...

subplot(2,1,2)
Hp_f2mass=fill(x_mass+x(1),y_mass,'b');