Check for 3D line plot to form a closed loop - randomly ordered points

Hi, I am using plot3 command to form a closed loop of points for a code. How can i determine automatically if the points form a closed loop without manually visualizing it. Attached is an example of the points which form the closed loop. I want to write a piece of code which can automatically determine if the points form a closed loop or not. The points are plotted in random order.

[Stephen23]

Duplicate:

https://www.mathworks.com/matlabcentral/answers/321341-check-for-3d-line-plot-to-form-a-closed-loop