The systematic potential design is of high importance in computational electromagnetics. For example, it is well known that when the efficient eddy-current formulations based on a magnetic scalar potential are employed in problems which involve conductive regions with holes, the so-called thick cuts are needed to make the boundary value problem well defined. Therefore, a considerable effort has been invested over the past twenty-five years to develop fast and general algorithms to compute thick cuts automatically. Nevertheless, none of the approaches proposed in literature meet all the requirements of being automatic, computationally efficient and general. In this paper, an automatic, computationally efficient and provably general algorithm is presented. It is based on a rigorous algorithm to compute a cohomology basis of the insulating region with state-of-art reductions techniques-the acyclic sub-complex technique, among others-expressly designed for cohomology computations over simplicial complexes. Its effectiveness is demonstrated by presenting a number of practical benchmarks. The automatic nature of the proposed approach together with its low computational time enable the routinely use of cohomology computations in computational electromagnetics.
