Version 2 — RPExpand: Software for Riesz projection expansion of resonance phenomena

The software RPExpand, implemented in MATLAB®, provides modal expansions of physical observables in resonant systems, based on contour integrals. Version 2.0 improves the workflow and adds new features. In addition to the poles corresponding to eigenmodes of the systems, zeros of various quantities can be computed. Their derivatives are evaluated if the required information is supplied at the integration points. Furthermore, expansions based on quasinormal modes are supported.