摘要
该文通过对原有四叉树在结点分裂和索引对象的结点分配方法方面进行改进,使索引对象被合理地并且不重复地分配到四叉树中的各个树结点中,减少了信息冗余,结点分布更加合理,从而提高整个索引树的搜索效率。并以ESRISHAPE格式文件为例,详细探讨了改进的四叉树在地理信息系统(GIS)的空间选择查询(包括点查询和开窗查询)中的应用与实现算法。实践表明,该算法逻辑清晰,实现简单,查询高效,具有实用价值。
Through improvement of original quadtree on tree node split and assignment of indexed object to tree node,this paper assigns these indexed objects to all tree nodes in the quadtree reasonably and unrepeatably,which reduces the redundancy,makes tree nodes distribute more rational,and improves the search efficiency of the whole quadtreet.And with a case of ESRI Shape format file,discusses in detail the spatial select query algorithm in Geographic Information Systems (GIS)including point query and window query,based on the improved quadtree.The results of the experiment show that this algorithm is efficient ,simple and easy to realize,and has powerful practical merits.
出处
《计算机工程与应用》
CSCD
北大核心
2003年第13期58-61,共4页
Computer Engineering and Applications
基金
国家863高技术研究发展计划"空间信息智能网络搜索技术"课题(编号:2001AA135090)资助
