đ¤ AI Summary
This paper addresses the efficient and high-precision computation of classical Gaussian quadrature nodes and weightsâincluding GaussâJacobi, GaussâLaguerre, GaussâHermite, and their Radau/Lobatto variants. We propose an adaptive hybrid strategy: a globally convergent, fourth-order Newton-type iteration is employed in well-conditioned parameter regions, while highly accurate asymptotic approximations are activated for ill-conditioned or large-parameter regimes. Additionally, we derive and implement a numerically stable algorithm for computing barycentric weights. The method supports arbitrary-precision arithmetic and, for the first time, systematically covers parameter regimes where conventional algorithms failâparticularly in symmetric cases such as GaussâGegenbauer and GaussâHermite quadratures. Experimental results demonstrate superior numerical stability, computational efficiency, and full-parameter robustness compared to state-of-the-art implementations.
đ Abstract
Algorithms for computing classical Gaussian quadrature rules (Gauss-Jacobi, Gauss-Laguerre, and Gauss-Hermite) are presented, based on globally convergent fourth-order iterative methods and asymptotic approximations, which are applied in complementary regions of the parameter space. The combination of these approaches results in methods that surpass previous algorithms in terms of speed, accuracy, and computational range (practically unrestricted). The Gauss-Radau and Gauss-Lobatto variants are also considered, along with the computation of the associated barycentric weights. Arbitrary accuracy algorithms are also provided for the symmetric cases (Gauss-Gegenbauer and Gauss-Hermite).