A Rational Krylov Toolbox for MATLAB

1 Overview Thank you for your interest in the Rational Krylov Toolbox (RKToolbox). The RKToolbox is a collection of scientific computing tools based on rational Krylov techniques. The development started in 2013 and the current version 2.7 provides ˆ an implementation of Ruhe’s (block) rational Krylov sequence method [8, 9], allowing to control various options, including user-defined inner products, exploitation of complex-conjugate shifts, orthogonalization, rerunning [3], and parallelism [4], ˆ algorithms for the implicit and explicit relocation of the poles of a rational Krylov space [2], ˆ a collection of utility functions and a gallery of special rational functions (e.g., Zolotarev approximants), ˆ an implementation of RKFIT [2, 3], a robust algorithm for approximate rational least squares approximation, including automated degree reduction, *School of Mathematics, The University of Manchester, Alan Turing Building, Oxford Road, M13 9PL Manchester, United Kingdom, Correspondence: [email protected]