线要素任意范围接边算法的设计与实现

Design and achievement of edgematching algorithm of line features in arbitrary scope

本文在深入分析传统接边算法的缺陷后,提出了一种高效的任意范围接边算法。该算法通过对参与接边的要素类进行2次筛选,提取参与接边的要素,有效缩短了算法的执行时间;为了按照接边要素的空间邻近关系进行接边匹配,将接边要素和接边线的交点与接边线首点间的折线距离作为键值对接边要素信息进行排序,提高了接边匹配效率,并且能准确处理在接边线节点处接边的情形。并通过武汉市等高线数据更新的接边处理试验,验证了该算法的高效性与正确性。

After the deficiency of conventional edgematching algorithm was analyzed in this paper, an efficient edgematching algo- rithm in arbitrary scope was presented. Through filtering the participant feature classes twice, and then fetching the participant feature classes, this algorithm effectively shortened the executive time. However, in order to carry through edgematching according to the spa- tial vicinity relation of the participant feature classes, the distance between the intersection of edgematching features along with its line and the first point of edgematching line was taken as key value. Then by the key value, the information of edgematching feature could be sorted. In this way, the algorithm could get faster matching efficiency and deal with the condition that matching edges are outside the node of edgematching line. Finally, by the experimentation of updating the contour line of Wuhan city, the efficiency and accuracy of the agorithm were verified.