How to do an animated plot in matlab

Question

I was wondering if anyone knew how to do an animation plot of x = (dataset of 1000 points) y = (dataset of 1000 points) plot(x,y)

big problem is these are datasets that i am trying to plot , or x,y coordinates as opposed to a function which I would know how to plot via an animation.

I tried to do frames in a for loop but it gave me dots and didn't join them in a line graph so I couldn't really watch the path being traced out.

code I used was

for i = 1:length(DATASET1)
pause(0.1)
plot(DATASET1(i),DATASET2(i))
draw on
end

Answer 1

Looks like you were close. Not sure draw on is any command though.

See if the code here inspires you to solve your case -

%// Sample x and y values assumed for demo.
x = 1:1000;
y = x.^2;

%// Plot starts here
figure,hold on

%// Set x and y limits of the plot
xlim([min(x(:)) max(x(:))])
ylim([min(y(:)) max(y(:))])

%// Plot point by point
for k = 1:numel(x)
    plot(x(k),y(k),'-') %// Choose your own marker here

    %// MATLAB pauses for 0.001 sec before moving on to execue the next 
    %%// instruction and thus creating animation effect
    pause(0.001);     
end

Answer 2

If what you want is for the plot to "grow" point by point: the easiest way is to create an empty plot and then update its XData and YData properties at each iteration:

h = plot(NaN,NaN); %// initiallize plot. Get a handle to graphic object
axis([min(DATASET1) max(DATASET1) min(DATASET2) max(DATASET2)]); %// freeze axes
%// to their final size, to prevent Matlab from rescaling them dynamically 
for ii = 1:length(DATASET1)
    pause(0.01)
    set(h, 'XData', DATASET1(1:ii), 'YData', DATASET2(1:ii));
    drawnow %// you can probably remove this line, as pause already calls drawnow
end

Here's an example¹ obtained with DATASET1 = 1:100; DATASET2 = sin((1:100)/6);

---

^{1 In case someone's interested, the figure is an animated gif which can be created by adding the following code (taken from here) within the loop, after the drawnow line:}

  frame = getframe(1);
  im = frame2im(frame);
  [imind,cm] = rgb2ind(im,256);
  if ii == 1;
      imwrite(imind,cm,filename,'gif','Loopcount',inf);
  else
      imwrite(imind,cm,filename,'gif','WriteMode','append');
  end

Answer 3

Since R2014b, you can work with annimatedline object (doc and how-to) that is meant to handle animated graphs pretty well. Basically, the annimatedline object has a addpoints function that adds new points to the line without having to redefine the existing points, along with a clearpoints function that clears lines for more complex animations.

Here is an example:

h = animatedline;
axis([0,4*pi,-1,1])

x = linspace(0,4*pi,1000);
y = sin(x);
for k = 1:length(x)  
    addpoints(h,x(k),y(k));
    drawnow
end