• Corpus ID: 233207339

Quadrature at fake nodes

@inproceedings{Marchi2021QuadratureAF,
  title={Quadrature at fake nodes},
  author={Stefano De Marchi and Giacomo Elefante and Emma Perracchione and Davide Poggiali},
  year={2021}
}
We investigate the use of the so-called mapped bases or fake nodes approach in the framework of numerical integration. We show that such approach is able to mitigate the Gibbs phenomenon when integrating functions with steep gradients. Moreover, focusing on the optimal properties of the Chebyshev-Lobatto nodes, we are able to analytically compute the quadrature weights of the fake Chebyshev-Lobatto nodes. Such weights, quite surprisingly, coincide with the composite trapezoidal rule. Numerical… 

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