ARPIST: Provably accurate and stable numerical integration over spherical triangles

Journal Article · 06 September 2022 · Journal of Computational and Applied Mathematics

DOI: https://doi.org/10.1016/j.cam.2022.114822 · OSTI ID:2424687

Li, Yipeng  ^[1]; Jiao, Xiangmin  ^[2]

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1. Stony Brook University, NY (United States); Beijing Oneflow Technology Ltd. (China)
2. Stony Brook University, NY (United States)

Numerical integration on spherical triangles, including the computation of their areas, is a core computation in geomathematics. The commonly used techniques sometimes suffer from instabilities and significant loss of accuracy. We describe a new algorithm, called ARPIST, for accurate and stable integration of functions on spherical triangles. ARPIST is based on an easy-to-implement transformation to the spherical triangle from its corresponding linear triangle via radial projection to achieve high accuracy and efficiency. More importantly, ARPIST overcomes potential instabilities in computing the Jacobian of the transformation, even for poorly shaped triangles that may occur at poles in regular longitude-latitude meshes, by avoiding potential catastrophic rounding errors. We compare our proposed technique with L’Huilier’s Theorem for computing the area of spherical triangles, and also compare it with the recently developed LSQST method (Beckmann et al., 2014) and a radial-basis-function-based technique (Reeger and Fornberg, 2016) for integration of smooth functions on spherical triangulations. In conclusion, our results show that ARPIST enables better or comparable accuracy over previous methods while being easier to implement, significantly faster, and more tolerant of poor element shapes.

• Research Organization: US Department of Energy (USDOE), Washington, DC (United States). Office of Science, Advanced Scientific Computing Research (ASCR)
• Sponsoring Organization: USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR). Scientific Discovery through Advanced Computing (SciDAC)
• OSTI ID: 2424687
• Journal Information: Journal of Computational and Applied Mathematics, Journal Name: Journal of Computational and Applied Mathematics Vol. 420; ISSN 0377-0427
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English