“…These functions called Laplace interpolation function (or nonSibsonian interpolation function) [9,10] possess several useful properties like the Kronecker delta property, as Lagrange interpolation functions used in finite element method. Thanks to these properties, the essential boundary condition can be easily and accurately enforced [11,12], as in the finite element method. Meanwhile, the natural element method does not require extra effort to generate the background cell, because it utilize a set of Delaunay triangles, which are automatically identified in process of the basis function definition, as its background cell.…”