Seksjon for matematikk, FLU, Nord Universitet, N-8049 Bodø, Norway.
Department of Mathematics, School of Natural Sciences (SNS), National University of Sciences and Technology (NUST), Islamabad 44000, Pakistan.
PLoS One. 2019 Apr 18;14(4):e0215054. doi: 10.1371/journal.pone.0215054. eCollection 2019.
In this paper we apply some higher order symplectic numerical methods to analyze the dynamics of 3-site Toda lattices (reduced to relative coordinates). We present benchmark numerical simulations that has been generated from the HOMsPY (Higher Order Methods in Python) library. These results provide detailed information of the underlying Hamiltonian system. These numerical simulations reinforce the claim that the symplectic numerical methods are highly accurate qualitatively and quantitatively when applied not only to Hamiltonian of the Toda lattices, but also to other physical models. Excepting exactly integrable models, these symplectic numerical schemes are superior, efficient, energy preserving and suitable for a long time integrations, unlike standard non-symplectic numerical methods which lacks preservation of energy (and other constants of motion, when such exist).
在本文中,我们应用一些高阶辛数值方法来分析 3 位点 Toda 晶格(简化为相对坐标)的动力学。我们呈现了来自 HOMsPY(Python 中的高阶方法)库生成的基准数值模拟。这些结果提供了基础哈密顿系统的详细信息。这些数值模拟证实了辛数值方法不仅在应用于 Toda 晶格的哈密顿量时具有高度的准确性,而且在应用于其他物理模型时也是如此。除了完全可积模型之外,这些辛数值方案在长时间积分方面具有优越性、高效性、能量守恒性和适用性,而标准的非辛数值方法则缺乏能量守恒性(以及其他运动常数,当存在时)。