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arXiv · 2606.15703

Strong Stability Preserving Integrating Factor Runge-Kutta Methods for Differential Lyapunov Equations with Positivity Preservation

Wenhui Zhang·Rihui Lan·Xiaobo Jing
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Abstract

This paper introduces second- and third-order integrating factor strong stability preserving Runge-Kutta methods for solving differential Lyapunov equations. The proposed schemes break the traditional order barrier while rigorously preserving the symmetry and positive semidefiniteness (SPSD) of numerical solutions-an essential property for stability analysis and control-theoretic applications. Furthermore, we provide a rigorous error estimate for the second-order scheme. Numerical experiments validate the accuracy of the methods and their ability to maintain SPSD properties.

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Wenhui Zhang, Rihui Lan, Xiaobo Jing. 2026-06-14. Strong Stability Preserving Integrating Factor Runge-Kutta Methods for Differential Lyapunov Equations with Positivity Preservation. https://arxiv.org/abs/2606.15703

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