A linear combination of lagrange interpolation polynomial 插值多項式的線性組合
The convergence of interpolation polynomials based on unit roots 基于單位根上插值多項式的收斂性
Estimation of approximation order of lagrange interpolation polynomial after revised 插值多項式的收斂階的估計
Confluent interpolation polynomial 匯合內(nèi)插多項式
Research on emile borel ' s work on improving lagrange interpolation polynomial 對波萊爾改進(jìn)拉格朗日插值公式思想方法的研究
Convergence order of double variate combination trigonometric interpolation polynomials 二元組合型三角插值多項式的收斂階
The trigonometric interpolation polynomials ' simultaneous approximation of functions and their derivatives 三角插值多項式對函數(shù)及其導(dǎo)數(shù)的同時逼近
The errors in calculating derivatives for the gll collocation points are evaluated , which can be alleviated from o ( ( n4 ) to o ( ( n2 ) by the double - precision method proposed in the present paper , where ( denotes the machine precision and n the order of the interpolation polynomials in the elements 文中對gll配置點下的求導(dǎo)誤差進(jìn)行了分析,提出的雙精度方法可以將求導(dǎo)誤差從o ( ( n4 )減小到o ( ( n2 ) ,其中(為機(jī)器精度, n為單元內(nèi)插值多項式階數(shù)。
In the terms of interpolation , the image reconstructed from nearest interpolation or linear interpolation has good edge but serious noise ; reconstruction from 4 * 4cubic interpolation or three b - spline or three - order lagrange interpolations has better local character . 2 x 2cubic interpolations which has both better edge and local character is the ideal interpolation , the following is the basic principle during reconstruction : ( 1 ) the more width of interpolation , the more number of summation and the more order of interpolation polynomial , the higher of density resolution ; ( 2 ) the more of interpolation polynomial and width of interpolation , the more of reconstruction time simultaneously , aimed at eliminating the effects of noise contained in projection data , in this paper , author analysis cause and effects of common artifacts . importantly , discusses convolution back - projection reconstruction algorithm with a shift axis of rotation has been derived for correcting images that acquired with a divergence axis of rotation using the fan beam geometry with an angle - equaled detector 在ct圖像重建時,選擇有限帶寬窗有較好的空間分辨率,三角形窗有較好的密度分辨率,選擇余弦窗則使得空間分辨率與密度分辨率的折衷;從窗函數(shù)的頻譜角度來講,可以用于圖像重建的一個良好的卷積窗函數(shù)應(yīng)該具備以下條件: ( ? )小的3db帶寬b ,即最小的主瓣寬度; ( ? )最小的旁瓣最大峰值a ; ( ? )最大的旁瓣峰值衰減速度d ;就內(nèi)插函數(shù)而言,臨近點內(nèi)插與線性內(nèi)插重建圖像噪聲大,但有較好的邊緣與細(xì)節(jié); 4 4三次內(nèi)插、三次b -樣條與四次拉格朗日多項式內(nèi)插圖像平滑,局部特性較好。
A kind of operator of trigonometric interpolation polynomials with bivariate product was constructed based on an equidistant node set , so that the operator could be converged uniformly to bivariate continuous functions with periodicity of 27 on whole plane , and the convergence order of the approximation would be optimal for a body of functions with arbitrary - ordered continuous partial deritives 摘要構(gòu)造了一類基于等距結(jié)點組上的二元三角插值多項式算子,使得該算子在全平面上一致收斂到每個以2為周期的二元連續(xù)函數(shù),并且對具有任意階連續(xù)偏導(dǎo)數(shù)的函數(shù)全體的逼近具有最佳收斂階。