摘要
针对参数曲线/曲面重要细节特征处理的问题,提出带多个权值的、局部插值的几何迭代算法.首先将初始控制顶点分为插值点和非插值点2组,在调整不同的插值点时对调整向量赋予不同的权值,非插值点则不进行调整;然后给出算法的迭代矩阵并分析了收敛性;最后将文中算法推广到三维曲面情形.数值实例结果表明,通过适当地选取权值,该算法不仅可以灵活地处理曲线/曲面的局部细节特征,而且迭代产生的误差相对较小.
In order to deal with detail features of parameter curves and surfaces, one local interpolation type of geometric iterative approximation method with multiple weights is presented. Firstly, the initial data points are classified into two groups: interpolating points and noninterpolating points. For the interpolating points, different weights are distributed to the corresponding adjusting vectors. For the noninterpolating points, there is no adjustment. Then, the iteration matrix is given and the convergence is further analyzed. Finally, the method has been generalized to 3 D surfaces. The results of numerical examples show that, the method can deal with detail features flexibly and the iteration errors are relatively small.
引文
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