select and extract only some coordinates of a 3D object

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I have the following .txt file (Rx3 matrix).
rabbit = importdata("rabbit.txt");
figure
plot3(rabbit(:,1), rabbit(:,2), rabbit(:,3),'k.','Markersize',5)
grid off
axis equal
xlabel('x')
ylabel('y')
zlabel('z')
I want to be able to extract only the coordinates of some nodes such as this area:
xlim([-10 -4])
ylim([-6 0])
zlim([11 16])
Could also be useful something like this that I found at the following link.
  2 Comments
Fabio Freschi
Fabio Freschi on 23 Dec 2022
Do you want to use the mouse and click on each point? Or rather you want to extract the subset of nodes in the region you specified?
Alberto Acri
Alberto Acri on 23 Dec 2022
I want to extract the subset of nodes in the region you specified

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Accepted Answer

Fabio Freschi
Fabio Freschi on 23 Dec 2022
Is this what you are asking?
% your code
rabbit = importdata("rabbit.txt");
figure
plot3(rabbit(:,1), rabbit(:,2), rabbit(:,3),'k.','Markersize',5)
grid off
axis equal
xlabel('x')
ylabel('y')
zlabel('z')
% range
xRange = [-10 -4];
yRange = [-6 0];
zRange = [11 16];
% indices of points in the range
idx = rabbit(:,1) >= xRange(1) & rabbit(:,1) <= xRange(2) & ...
rabbit(:,2) >= yRange(1) & rabbit(:,2) <= yRange(2) & ...
rabbit(:,3) >= zRange(1) & rabbit(:,3) <= zRange(2);
% plot in red
hold on
plot3(rabbit(idx,1), rabbit(idx,2), rabbit(idx,3),'ro','Markersize',5)
  2 Comments
Alberto Acri
Alberto Acri on 23 Dec 2022
Yes exactly. However, can you tell me how to save the coordinates you selected in red in an array?
Fabio Freschi
Fabio Freschi on 23 Dec 2022
Sure! Simply get the coordinates that were plotted
rabbithead = [rabbit(idx,1), rabbit(idx,2), rabbit(idx,3)];

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