How to calculate the subtended angle ?

I want to calculate the angle between two lines in GUI

Answer 1

[Star Strider]

See my Answer to How can I calculate the angles between a polygons vertices? for an approach that appears to work.

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[Rami]

It worked , but if i want the calclated angle apper on the orignal figure rather than ploting another figure . I am doing it on GUI

[Star Strider]

I have very little experience with GUIs, and none of the code being used to generate the figures.

Remember to include the axes handle (gca) in the plot arguments to specify the axes being modified.

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