On Construction of High Order Exponentially Fitted Methods Based on Parameterized Rational Approximations to exp(q)
-
摘要: 得到了指数函数exp(q)的含双参数α、β的(4,4)有理逼近的表达式及其为A-可接受的充要条件,由此构造了精确阶可达6至8阶的四阶导数单步指数拟合方法与三阶导数混合单步指数拟合方法.研究了这两种算法的拟合阶及其为A-稳定的充要条件.最后讨论了四阶导数方法的中间性与误差界.Abstract: By the discussion of the formula and properties of(4,4) parametric form rational approximation to function exp(q),the fourth order derivative one-step exponentially fitted method and the third order derivative hybrid one-step exponentially fitted method are presented,their order p satisfying 6≤p≤8.The necessary and sufficient conditions for the two methods to be A-stable are given.Finally,for the fourth order derivative method,the error bound and the necessary and sufficient conditions for it to be median are discussed.
-
Key words:
- exponentially fitted method /
- order /
- A-stability
-
[1] Liniger W.Global accuracy and A-stability of one-and two-step integration formulae forstiff ordinary differential equations[A].In:John,L.Morris Ed.Conference on Numerical Solution of Differential Equations[C],Dundee:Springer-Verlag,1969,188~193. [2] Liniger W,Willoughby R A.Efficient integration methods for stiff systems of ordinary differential equations[J].S I A M J Numer Anal,1970,7(1):47~66. [3] 杨逢建.怎样求函数exp(q)的有理逼近[J].湘潭师范学院学报,1990,10(3):24~32. [4] 李寿佛,杨逢建.函数exp(q)的可接受有理逼近[J].计算数学,1992,14(4):480~488. [5] 袁兆鼎,费景高,刘德贵.刚性常微分方程初值问题的数值解法[M].北京:科学出版社,1987. [6] Lambert J D.Computational Methodsin Ordinary Differential Equations[M].New York:Wiley,1973.
计量
- 文章访问数: 2279
- HTML全文浏览量: 31
- PDF下载量: 694
- 被引次数: 0