Editing Numerical integration (section)

=== Extrapolation methods ===
The accuracy of a quadrature rule of the [[Newton–Cotes formulas|Newton–Cotes]] type is generally a function of the number of evaluation points. The result is usually more accurate as the number of evaluation points increases, or, equivalently, as the width of the step size between the points decreases. It is natural to ask what the result would be if the step size were allowed to approach zero. This can be answered by extrapolating the result from two or more nonzero step sizes, using [[series acceleration]] methods such as [[Richardson extrapolation]]. The extrapolation function may be a [[polynomial]] or [[rational function]]. Extrapolation methods are described in more detail by Stoer and Bulirsch (Section 3.4) and are implemented in many of the routines in the [[QUADPACK]] library.