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Adaptive Simpson's method, also called adaptive Simpson's rule, is a method of numerical integration proposed by G.F. Kuncir in 1962. It is probably the first recursive adaptive algorithm for numerical integration to appear in print,〔For an earlier, non-recursive adaptive integrator more reminiscent of ODE solvers, see 〕 although more modern adaptive methods based on Gauss–Kronrod quadrature and Clenshaw–Curtis quadrature are now generally preferred. Adaptive Simpson's method uses an estimate of the error we get from calculating a definite integral using Simpson's rule. If the error exceeds a user-specified tolerance, the algorithm calls for subdividing the interval of integration in two and applying adaptive Simpson's method to each subinterval in a recursive manner. The technique is usually much more efficient than composite Simpson's rule since it uses fewer function evaluations in places where the function is well-approximated by a cubic function. A criterion for determining when to stop subdividing an interval, suggested by J.N. Lyness, is : where is an interval with midpoint , , , and are the estimates given by Simpson's rule on the corresponding intervals and is the desired tolerance for the interval. Simpson's rule is an interpolatory quadrature rule which is exact when the integrand is a polynomial of degree three or lower. Using Richardson extrapolation, the more accurate Simpson estimate for six function values is combined with the less accurate estimate for three function values by applying the correction . The thus obtained estimate is exact for polynomials of degree five or less. ==Sample implementations == 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Adaptive Simpson's method」の詳細全文を読む スポンサード リンク
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