A memory-efficient sparse direct solver with applications in CEM

A memory-efficient exact arithmetic direct solution method for sparse linear systems arising from the Finite Element Method (FEM) is outlined. The proposed method is based on a novel symmetric domain decomposition method (DDM) with one set of Lagrange multipliers that is applicable to a large class of methods arising from the Galerkin partial differential equations (PDEs). Comparisons with state-of-the-art exact direct solvers on several electrically large problems suggest up to 8 times memory improvement, while remaining competitive in runtime, and achieving the same accuracy (more than 12 correct digits).