Using the Rd Rational Arnoldi Method for Exponential Integrators
نویسنده
چکیده
In this paper we investigate some practical aspects concerning the use of the Restricted-Denominator (RD) rational Arnoldi method for the computation of the core functions of exponential integrators for parabolic problems. We derive some useful a-posteriori bounds together with some hints for a suitable implementation inside the integrators. Numerical experiments arising from the discretization of sectorial operators are presented.
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