Solving linear systems over idempotent semifields through LU-factorization

In this paper, we introduce and analyze a new LU-factorization technique for square matrices over idempotent semifields. In particular, more emphasis is put on “max-plus” algebra here but the work is extended to other idempotent semifields as well. We first determine the conditions under which a square matrix has LU factors. Next, using this technique, we propose a method for solving square linear systems of equations whose system matrices are LU-factorizable. We also give conditions for an LU-factorizable system to have solutions. This work is an extension of similar techniques over fields. Maple® procedures for this LU-factorization are also included.