没文化的用GIS做个地图都丢三落四的。 数字是啥意思？ populaiton count or

population density? what is the enunmeration unit (county? zip code? ) what data classification method? Obviously, it is not equal interval. Is it quantile? standard devision? mantual interval? geometric interval? natual break?   这些信息， 地图上本该明确表明的。