基于二维哈希表的海量高程点数据去重算法设计  

Duplication deletion algorithm based on two-dimensional Hashtable for multitudinous elevation points data

作　　者：张蒙[1] 康建荣[1] 贾莹媛[2] 刘翘楚[3] 

机构地区：[1]江苏师范大学测绘学院,江苏徐州221116 [2]河海大学地球与工程学院,南京210098 [3]连云港市国土资源局,江苏连云港222000

出　　处：《测绘科学》2013年第6期118-119,142,共3页Science of Surveying and Mapping

基　　金：国家自然科学基金项目(51074139)

摘　　要：由高程点数据构建的不规则三角网(TIN)是地形图最基本及最主要的数字高程模型(DEM)。重复的高程点会使TIN构网过程中产生错误,不能生成TIN,所以在构建TIN前必须对原始高程点数据进行去重。本文改进传统的基于一维哈希表的哈希算法,采用二维哈希表对数据进行去重,在内存需求和运算速度上有较大优势,有着良好的时效性及准确度。TIN is the most basic and main DEM of topographic map. The repeated elevation points cause error in TIN triangulation creation process, so before the construction of TIN, the repeated points must be deleted for original elevation point data. This article improved the traditional method which is based on the unidimensional Hash-table, adopted the two-dimensional Hash-table to do the duplication deletion. This method has advantages in the memory requirements and arithmetic speed with high timeliness and accuracy.

关 键 词：哈希算法 二维哈希表 高程点 去重 大批量数据 

分 类 号：P208[天文地球—地图制图学与地理信息工程] TP391[天文地球—测绘科学与技术]