{ "id": "2110.01372", "version": "v2", "published": "2021-09-18T19:31:21.000Z", "updated": "2024-03-24T15:16:06.000Z", "title": "Legendre Expansions of Products of Functions with Applications to Nonlinear Partial Differential Equations", "authors": [ "Rabia Djellouli", "David Klein", "Matthew Levy" ], "comment": "38 pages, 25 figures", "journal": "Applied Numerical Mathematics, Vol. 201, p. 301-321 (2024)", "doi": "10.1016/j.apnum.2024.03.014", "categories": [ "math.NA", "cs.NA" ], "abstract": "Given the Fourier-Legendre expansions of $f$ and $g$, and mild conditions on $f$ and $g$, we derive the Fourier-Legendre expansion of their product in terms of their corresponding Fourier-Legendre coefficients. In this way, expansions of whole number powers of $f$ may be obtained. We establish upper bounds on rates of convergence. We then employ these expansions to solve semi-analytically a class of nonlinear PDEs with a polynomial nonlinearity of degree 2. The obtained numerical results illustrate the efficiency and performance accuracy of this Fourier-Legendre based solution methodology for solving an important class of nonlinear PDEs.", "revisions": [ { "version": "v2", "updated": "2024-03-24T15:16:06.000Z" } ], "analyses": { "subjects": [ "42C10", "41A25", "65L06", "65N35", "40-08" ], "keywords": [ "nonlinear partial differential equations", "legendre expansions", "fourier-legendre expansion", "applications", "nonlinear pdes" ], "tags": [ "journal article" ], "publication": { "publisher": "Elsevier" }, "note": { "typesetting": "TeX", "pages": 38, "language": "en", "license": "arXiv", "status": "editable" } } }