Polezzi, M.Ranga, A. Sri2014-05-202014-05-202007-03-15Journal of Computational and Applied Mathematics. Amsterdam: Elsevier B.V., v. 200, n. 2, p. 576-590, 2007.0377-0427http://hdl.handle.net/11449/35282We improve upon the method of Zhu and Zhu [A method for directly finding the denominator values of rational interpolants, J. Comput. Appl. Math. 148 (2002) 341-348] for finding the denominator values of rational interpolants, reducing considerably the number of arithmetical operations required for their computation. In a second stage, we determine the points (if existent) which can be discarded from the rational interpolation problem. Furthermore, when the interpolant has a linear denominator, we obtain a formula for the barycentric weights which is simpler than the one found by Berrut and Mittelmann [Matrices for the direct determination of the barycentric weights of rational interpolation, J. Comput. Appl. Math. 78 (1997) 355-370]. Subsequently, we give a necessary and sufficient condition for the rational interpolant to have a pole. (c) 2006 Elsevier B.V. All rights reserved.576-590enginterpolationrational interpolantsdenominator valuesbarycentric weightsArtigo10.1016/j.cam.2006.01.013WOS:000244279500010Acesso abertoWOS000244279500010.pdf3587123309745610