DEIP, discontinuous element insertion Program - Mesh generation for interfacial finite element modeling. The Discontinuous Element Insertion Program is a MATLAB/Octave toolbox for inserting zero-thickness interface elements into two and three dimensional finite element meshes. These interface elements, termed herein as “couplers”, are used for intrinsic cohesive zone modeling and for the Discontinuous Galerkin method. The underlying algorithm is topology based and is suitable for complex, unstructured meshes of mixed-type linear and quadratic elements. Insertion is specified according to regions or subdomains within the overall analysis domain, a geometrically intuitive means to designate the coupler locations.