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但测绘部门建立的地形图数据库多为单纯的制图数据，虽然与GIS数据一样是矢量结构，却无法直接输入GIS以满足应用需要。
But most of topographical map database produced by survey department is only cartographic data, which is vector data structure, but cannot be imported into GIS directly to meet GIS using.
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