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1.
关于Newton—Thiele型二元有理插值的存在性问题   总被引:1,自引:1,他引:0  
基于均差的牛顿插值多项式可以递归地实现对待插值函数的多项式逼近,而Thiele型插值连分式可以构造给定节点上的有理函数。将两者结合可以得到Newton-Thiele型二元有理插值(NTRI)算法,本文解决了NTRI算法的存在性问题,并有数值例子加以说明。  相似文献   

2.
有理插值比多项式插值有更好的近似,但有理插值一般很难控制极点的产生.基于Thiele型连分式插值与重心有理插值,构造三元重心Thiele型混合有理插值,当选取适当的权后能避免部分极点的产生.文章最后通过数值例子验证了这种方法的正确性和有效性.  相似文献   

3.
本文以 Newton插值及 Thiele型连分式插值为基础 ,将线性与非线性插值方法相结合 ,通过混合差商的定义 ,给出了三元 Newton-Thiele型插值公式及误差估计式 .  相似文献   

4.
二元切触有理插值是有理插值的一个重要内容,而降低其函数的次数和解决其函数的存在性是有理插值的一个重要问题.二元切触有理插值算法的可行性大都是有条件的,且计算复杂度较大,有理函数的次数较高.利用二元Hermite(埃米特)插值基函数的方法和二元多项式插值误差性质,构造出了一种二元切触有理插值算法并将其推广到向量值情形.较之其它算法,有理插值函数的次数和计算量较低.最后通过数值实例说明该算法的可行性是无条件的,且计算量低.  相似文献   

5.
本以Newton插值及Thiele型连分式插值为基础,其线性与非线性插值方法相结合,通过混合差商的定义,给出了三元Newton-Thiele型插值公式及误差估计式。  相似文献   

6.
郑涛  唐烁  余小磊 《大学数学》2013,29(2):50-55
利用Samelson型矩阵广义逆,构造了一种基于Thiele型连分式插值与重心有理插值的相结合的二元矩阵值混合有理插值格式,这种新的混合矩阵值有理插值函数继承了连分式插值和重心插值的优点,它的表达式简单,计算方便,数值稳定性好.该算法满足有理插值问题所给的插值条件,同时给出了误差估计分析.最后用数值算例验证了插值算法的有效性.  相似文献   

7.
切触有理插值是函数逼近的一个重要内容,而降低切触有理插值的次数和解决切触有理插值函数的存在性是有理插值的一个重要问题.切触有理插值函数的算法大都是基于连分式进行的,其算法可行性是有条件的,且计算量较大.利用Newton(牛顿)多项式插值的承袭性和分段组合的方法,构造出了一种无极点且满足高阶导数插值条件的切触有理插值函数,并推广到向量值切触有理插值情形;既解决了切触有理插值函数存在性问题,又降低了切触有理插值函数的次数.最后给出误差估计,并通过数值实例说明该算法具有承袭性、计算量低、便于编程等特点.  相似文献   

8.
利用二元Lagrange插值公式对一类二元有理插值函数的存在性给出了一个判别方法,并在判别出该二元有理插值函数存在时,给出了它的表现公式。此外,对导致二元有理插值函数不存在的不可达点,本文给出了一种处理方法,使之由不可达点变成可达点。文章的最后还给出若干数值例子说明了本方法的有效性.  相似文献   

9.
二元Thiele型向量有理插值   总被引:19,自引:3,他引:16  
朱功勤  顾传青 《计算数学》1990,12(3):293-301
本文对二元Thiele型连分式的渐近分式施行Samelson逆变换,建立了平面矩形域上的二元向量值有理插值,所得结果是一元向量值有理插值的推广和改进.  相似文献   

10.
提出了一种基于Taylor算子的二元向量切触有理插值的新方法.首先应用已知的节点定义各阶有理插值基函数,再用相应的向量值和各阶偏导数值建立一种类似二元函数Taylor公式的新型插值算子,最后进行组合运算,得出二元向量一阶、二阶切触有理插值函数的显式表达式,并自然推广到k阶情形,还给出了误差估计.算例表明,该方法计算简单,过程公式化,有应用价值.  相似文献   

11.
修正的 Thiele-Werner型有理插值   总被引:1,自引:0,他引:1  
Through adjusting the order of interpolation nodes, we gave a kind of modified Thiele-Werner rational interpolation. This interpolation method not only avoids the infinite value of inverse differences in constructing the Thiele continued fraction interpolation, but also simplifies the interpolating polynomial coefficients with constant coefficients in the Thiele-Werner rational interpolation. Unattainable points and determinantal expression for this interpolation are considered. As an extension, some bivariate analogy is also discussed and numerical examples are given to show the validness of this method.  相似文献   

12.
COMPUTATION OF VECTOR VALUED BLENDING RATIONAL INTERPOLANTS   总被引:3,自引:0,他引:3  
As we know, Newton's interpolation polynomial is based on divided differences which can be calculated recursively by the divided-difference scheme while Thiele 's interpolating continued fractions are geared towards determining a rational function which can also be calculated recursively by so-called inverse differences. In this paper, both Newton's interpolation polynomial and Thiele's interpolating continued fractions are incorporated to yield a kind of bivariate vector valued blending rational interpolants by means of the Samelson inverse. Blending differences are introduced to calculate the blending rational interpolants recursively, algorithm and matrix-valued case are discussed and a numerical example is given to illustrate the efficiency of the algorithm.  相似文献   

13.
After recalling some pitfalls of polynomial interpolation (in particular, slopes limited by Markov's inequality) and rational interpolation (e.g., unattainable points, poles in the interpolation interval, erratic behavior of the error for small numbers of nodes), we suggest an alternative for the case when the function to be interpolated is known everywhere, not just at the nodes. The method consists in replacing the interpolating polynomial with a rational interpolant whose poles are all prescribed, written in its barycentric form as in [4], and optimizing the placement of the poles in such a way as to minimize a chosen norm of the error. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

14.
根据伪多元函数的特性,主要讨论了伪多元函数的Thiele型有理插值,并给出了Thiele型有理插值的误差.  相似文献   

15.
《分析论及其应用》2016,32(1):65-77
General interpolation formulae for barycentric interpolation and barycentric rational Hermite interpolation are established by introducing multiple parameters,which include many kinds of barycentric interpolation and barycentric rational Hermite interpolation. We discussed the interpolation theorem, dual interpolation and special cases. Numerical example is given to show the effectiveness of the method.  相似文献   

16.
An algorithm incorporating features essential for practical,reliable, rational interpolation is explained. This algorithmgenerates a Thiele-Werner continued fraction representationof the interpolant. A backward error analysis is presented forthe algorithm, as well as for its special cases of Newton polynomialinterpolation and Thiele rational interpolation. This is madepossible by introducing into the Newton method, Thiele methodand Werner method a strategy for selecting the interpolationpoints in an optimal order.  相似文献   

17.
有理反插值     
在解决反插值问题时,本文首次利用Thiele型连分式有理插值,得到了两种十分有效的方法:函数插值的有理反插法和反函数的有理插值法,同多项式反插值相比有较好的效果.数值例子说明了在解代数方程时有理反插法优于多项式反插法.  相似文献   

18.
Among the representations of rational interpolants, the barycentric form has several advantages, for example, with respect to stability of interpolation, location of unattainable points and poles, and differentiation. But it also has some drawbacks, in particular the more costly evaluation than the canonical representation. In the present work we address this difficulty by diminishing the number of interpolation nodes embedded in the barycentric form. This leads to a structured matrix, made of two (modified) Vandermonde and one Löwner, whose kernel is the set of weights of the interpolant (if the latter exists). We accordingly modify the algorithm presented in former work for computing the barycentric weights and discuss its efficiency with several examples.  相似文献   

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