Discrete weighted least-squares method for the Poisson and biharmonic problems on domains with smooth boundary

In this article a discrete weighted least-squares method for the numerical solution of elliptic partial differential equations exhibiting smooth solution is presented. It is shown how to create well-conditioned matrices of the resulting system of linear equations using algebraic polynomials, carefully selected matching points and weight factors. Two simple algorithms generating suitable matching points, the Chebyshev matching points for standard two-dimensional domains and the approximate Fekete points of Sommariva and Vianello for general domains, are described. The efficiency of the presented method is demonstrated by solving the Poisson and biharmonic problems with the homogeneous Dirichlet boundary conditions defined on circular and annular domains using basis functions in the form satisfying and in the form not satisfying the prescribed boundary conditions.

[1]  Wilhelm Heinrichs,et al.  Improved Lebesgue constants on the triangle , 2005 .

[2]  Discrete least‐squares global approximations to solutions of partial differential equations , 1991 .

[3]  Marco Vianello,et al.  A Numerical Study of the Xu Polynomial Interpolation Formula in Two Variables , 2005, Computing.

[4]  Mark A. Taylor,et al.  An Algorithm for Computing Fekete Points in the Triangle , 2000, SIAM J. Numer. Anal..

[5]  Pavel B. Bochev,et al.  Finite Element Methods of Least-Squares Type , 1998, SIAM Rev..

[6]  Jan S. Hesthaven,et al.  From Electrostatics to Almost Optimal Nodal Sets for Polynomial Interpolation in a Simplex , 1998 .

[7]  Tim Warburton,et al.  An explicit construction of interpolation nodes on the simplex , 2007 .

[8]  T. Tran-Cong,et al.  A Cartesian‐grid collocation method based on radial‐basis‐function networks for solving PDEs in irregular domains , 2007 .

[9]  Alvise Sommariva,et al.  Computing approximate Fekete points by QR factorizations of Vandermonde matrices , 2009, Comput. Math. Appl..

[10]  Marco Vianello,et al.  Bivariate polynomial interpolation on the square at new nodal sets , 2005, Appl. Math. Comput..

[11]  Yuan Xu,et al.  Lecture notes on orthogonal polynomials of several variables , 2004 .

[12]  Mark A. Taylor,et al.  Tensor product Gauss-Lobatto points are Fekete points for the cube , 2001, Math. Comput..

[13]  Weiwei Sun,et al.  Nonconforming spline collocation methods in irregular domains , 2007 .

[14]  Víctor Pereyra,et al.  Least squares collocation solution of elliptic problems in general regions , 2006, Math. Comput. Simul..

[15]  L. P. BOS,et al.  On the Calculuation of Approximate Fekete Points: the Univariate Case , 2008 .

[16]  Enrique Bendito,et al.  Estimation of Fekete points , 2007, J. Comput. Phys..

[17]  G. Pinder,et al.  Least squares collocation solution of differential equations on irregularly shaped domains using orthogonal meshes , 1989 .

[18]  Ivo Babuška,et al.  Approximate optimal points for polynomial interpolation of real functions in an interval and in a triangle , 1995 .

[19]  Mark G. Blyth,et al.  A Lobatto interpolation grid over the triangle , 2006 .

[20]  P. Grisvard Elliptic Problems in Nonsmooth Domains , 1985 .

[21]  Marco Vianello,et al.  Bivariate Lagrange interpolation at the Padua points: the ideal theory approach , 2007, Numerische Mathematik.