People do n ' t want gis only to show map simply and to make map automatically . people expect to get more knowledge from it . so dm ( data mining ) and idss ( intelligent decision support system ) are imported into gis 人们对gis的要求已经不再局限于简单的图层显示和自动制图，人们期望从中获得更多的知识，因而提出了将数据挖掘、智能决策引入gis中。
