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A least squares radial basis function finite difference method with improved stability properties

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 نشر من قبل Igor Tominec
 تاريخ النشر 2020
  مجال البحث الهندسة المعلوماتية
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Localized collocation methods based on radial basis functions (RBFs) for elliptic problems appear to be non-robust in the presence of Neumann boundary conditions. In this paper we overcome this issue by formulating the RBF-generated finite difference method in a discrete least-squares setting instead. This allows us to prove high-order convergence under node refinement and to numerically verify that the least-squares formulation is more accurate and robust than the collocation formulation. The implementation effort for the modified algorithm is comparable to that for the collocation method.

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