矢量或栅格操作函数,包括按区域伸缩栅格像元值、局域统计、按矢量图形裁剪栅格、矢量化栅格等。...|两边图形是否竖直对齐select point '(0,1)' ?| point '(0,0)';t?-|是否垂直select lseg '((0,0),(0,1))' ?...path转换为闭合pathselect pclose(path '[(0,0),(1,1),(2,0)]');((0,0),(1,1),(2,0))popen(path)path将闭合path转换为开放...转多边形select polygon(path ‘((0,0),(1,1),(2,0))’);((0,0),(1,1),(2,0))PostGIS 系统表查看spatial_ref_sys表在基于PostGIS...dropoff_geom | 2 | 2163 | POINTPostGIS 两个重要的坐标体系4326 \ GCS_WGS_1984 \ Geographic Coordinate System(GCSS)地理坐标系