This paper discusses the polygon medial axis definition of gis and calculation geometry , and their main distinguishing feature , pointes out that the polygon medial axis should be the locu of the equal - distance points to two or more edges of the polygon ; analyzes the relevant different algorithm and cases in practice , and proposes the geometry means in theory relatively rigid and widely meeting the requirements in practice - dotted pair rank method and the map algebra polygon medial axis method , utilizes them to offer several polygon medial axis calculation examples 摘要比較了當前國內外gis中和計算幾何中關于多邊形中軸的定義,討論了它們的主要特點,指出多邊形中軸應是到兩個以上邊距離相等點的軌跡,并據此分析了相應的各種算法和實際應用場合,提出了理論上較為嚴密、能夠廣泛滿足實際應用需要的幾何方法點對序列法和地圖代數多邊形中軸法。