How to determine whether V3 is between V1 and V2 when we go from V1 to V2 counterclockwise?

Question

I have three vectors V1, V2, and V3. Their origin points are on the axes\' origin. How could I determine whether V3 is between V1 and V2 when I move around counterclockwise

Answer 1

V1 is a red herring. You're just going to confuse yourself thinking about 3 angles at once.

2. Rotate everything clockwise by angle(V1)
3. Normalize the remaining two angles to [0,360)

Now the question is simply to compare norm(angle(V2)-angle(V1)) and norm(angle(V3)-angle(V1)).