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Deleting circles drawn using viscircles

Asked by Vance Blake on 19 Aug 2019
Latest activity Commented on by Vance Blake on 13 Sep 2019 at 22:37
Hello, I am trying to delete a group of circles drawn on my plot using viscircles. I have saved the group to a handle, but when I try to execute the delete(handle) command the circles still remain. I am using 'hold on' to continuously update the same figure could that be interfering? The points that the circles surround are removed when I delete their handle. below is a picture of before and after I run the delete(handle) commands. Would usign data linking/sourcing be a better option?? Would showing the updates via a new subplot window also work ??
Before:
After:

  2 Comments

Adam
on 19 Aug 2019
Deleting handles returned from viscircles works fine when I try it, but I don't know how you are using it specifically.
I am using viscircles to place circles around the points on the plot. I have all the circles saved to a handle called CTR_circles1 but when i delete CTR_circles1 the circles don't disappear. the relevant parts of the code are shown below. I do this task many more times thorughout the code but for the initial time I want to use it, it doesn't work.
% plots circles centered around the randomly generated points
for i = 1:n
radii_node = 4;
centers_node = [x(i), y(i)];
CTR_circles1 = viscircles(centers_node, radii_node, 'color', 'r');
hold on
end
%%
delete(CTR_circles1);

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1 Answer

Answer by Adam Danz
on 19 Aug 2019
Edited by Adam Danz
on 20 Aug 2019 at 23:11
 Accepted Answer

The handles are being overwritten on each iteration of the i-loop so at the end of the loop, you only have access to the last drawn cirlcle(s).
Instead,
% plots circles centered around the randomly generated points
CTR_circles1 = gobjects(1,n); % or (n,1)
hold on
for i = 1:n
radii_node = 4;
centers_node = [x(i), y(i)];
CTR_circles1(i) = viscircles(centers_node, radii_node, 'color', 'r');
end
%%
delete(CTR_circles1);
Or better yet, use input matrices to avoid the loop.
centers_node = [x(:), y(:)];
radii_node = 4 * ones(size(centers_node,1),1);
CTR_circles1 = viscircles(centers_node, radii_node, 'color', 'r');

  24 Comments

Hey Adam, Happy Friday! Just wondering but I wanted to put annotations/text boxes at specific coordinates but when I read up on the page I saw that the values of x and y in the 'dim' vector must be between 0 and 1. Im just looking for a way to place 'X's at specific xy coordinates to signify that those points are no longer being considered for my calculations?? I figured annotations would be good way to accomplish that because I wanted to avoid matlab cconsidering a plotted X as an active point and therefore valid for my calculations. If you have any work arounds or suggestions Im all ears. Have a great weekend!
Adam Danz
on 13 Sep 2019 at 21:49
How about we start a new question since we've diverged a bit from the original topic which may make the thread difficult to follow?

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