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arXiv · 2404.19407

Comparison of two numerical methods for Riemannian cubic polynomials on Stiefel manifolds

Alexandre Anahory Simoes·Leonardo Colombo·Fátima Silva Leite
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Abstract

In this paper we compare two numerical methods to integrate Riemannian cubic polynomials on the Stiefel manifold $\textbf{St}_{n,k}$. The first one is the adjusted de Casteljau algorithm, and the second one is a symplectic integrator constructed through discretization maps. In particular, we choose the cases of $n=3$ together with $k=1$ and $k=2$. The first case is diffeomorphic to the sphere and the quasi-geodesics appearing in the adjusted de Casteljau algorithm are actually geodesics. The second case is an example where we have a pure quasi-geodesic different from a geodesic. We provide a numerical comparison of both methods and discuss the obtained results to highlight the benefits of each method.

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Alexandre Anahory Simoes, Leonardo Colombo, Fátima Silva Leite. 2024-04-30. Comparison of two numerical methods for Riemannian cubic polynomials on Stiefel manifolds. https://arxiv.org/abs/2404.19407

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