Given a set of N points in general position on the plane, the problem is to give efficient algorithms to find
- the smallest semicircular region (semidisk) that contains the points
- the smallest circular segment that contains the points (2 variants - 'smallest' could mean either of 'least area' or 'least perimeter').
- the smallest sector that contains the points (again, 2 variants)
I am not aware of previous works on these questions.
Note: An O(N^2) algorithm for question 1 has been proposed in https://arxiv.org/abs/2005.10245. No proof of optimality was given, so there could be faster algorithms.
Some thoughts on question 2 are also given there but no algorithm.
Higher dimensional analogs of these questions - hemisphere, spherical segment etc..- arise naturally.