This paper deals with the derivation of asymptotic expressions for the quadrature error of Gauss–Radau–Jacobi and Gauss–Radau–Laguerre formulas. Starting from the contour integral representation of the remainder term, the analysis is derivative-free and based on the theory of analytic functions. The final error estimates allow to select a-priori the number of quadrature points necessary to achieve a prescribed accuracy. Several numerical examples are reported.
