  We study the problem of multiway number partition optimization, which has a
myriad of applications in the decision, learning and optimization literature.
Even though the original multiway partitioning problem is NP-hard and requires
exponential time complexity algorithms; we formulate an easier optimization
problem, where our goal is to find a solution that is locally optimal. We
propose a linearithmic time complexity $O(N\log N)$ algorithm that can produce
such a locally optimal solution. Our method is robust against the input and
requires neither positive nor integer inputs.
