Some remarks on the numerical computation of integrals on an unbounded interval

An account of the error and the convergence theory is given for Gauss-Laguerre and Gauss-Radau-Laguerre quadrature formulae. We develop also truncated models of the original Gauss rules to compute integrals extended over the positive real axis. Numerical examples confirming the theoretical results are given comparing these rules among themselves and with different quadrature formulae proposed by other authors (Evans, Int. J. Comput. Math. 82:721-730, 2005; Gautschi, BIT 31:438-446, 1991).