关于Arcinfo几种地图格式的说明-frost.wrath-ChinaUnix博客

Arcinfo做为GIS行业的老大，常用三种地图格式为：Coverage、Shape、E00。

Coverage：是Arcinfo WorkStation的专用地图格式，也是Arcinfo最老的地图格式，分点、线、面三个图层，附带图层的各个属性，以紧密的拓扑关系为基础。由于这种格式过于庞大，对于数据交换以及地图发布不方便，已经渐渐被Shape和其它格式所替代。不过一些大型国家机构的原始数据仍然采用Coverage格式。

E00：是一种通用格式，可以把Arcinfo的各种数据以这种通用格式输出，以便别的软件（如ENVI）方便访问，和mapinfo 的MIF文件功能相同。我觉得一个好处就是一个数据集只用一个文件表示，容易拷贝和存储，而不用考虑 Coverage INFO文件夹里的INFO文件。

Shape：是Arcview提供的结构简练的桌面标准数据格式，也是这几年来ESRI主要推广的地图格式。它也是按照点、线、面来存储地图数据，其它附属信息存放在点、线、面图层所对应的mdb文件中。它的优点在于继承了Coverage格式的大多数特点，并减少了存储空间，对OpenGIS和WebGIS的发展给予了更好的支持。

说明：这三种格式在ESRI Arcinfo的各个产品中都有很好的支持，并提供Arctools中的转换工具对这几种格式进行相互转换。ArcSDE和MapObjects更是全面兼容，所以使用ArcSDE来存储这几种地图格式，再不考虑数据统一性的情况下不会有问题。

The format is relatively straight-forward: the first six lines indicate the reference of the grid, followed by the values listed in the order they would naturally appear (left-right, top-down). For example, consider a grid, shown to the right. This could be encoded into an ASCII grid file, that would look like:

Grid image

Values

ASCII grid format

	25	75	125	175
275	NA	NA	5	2
225	NA	20	100	36
175	3	8	35	10
125	32	42	50	6
75	88	75	27	9
25	13	5	1	NA

ncols         4
nrows         6
xllcorner     0.0
yllcorner     0.0
cellsize      50.0
NODATA_value  -9999
-9999 -9999 5 2
-9999 20 100 36
3 8 35 10
32 42 50 6
88 75 27 9
13 5 1 -9999

where

ncols and nrows are the numbers of rows and columns, respectively (represented as );
xllcorner and yllcorner are the western (left) x- and southern (bottom) y-coordinates, such as (represented as with an optional decimal point)
cellsize is the of one side of a square cell (a real number); and,
nodata_value is the value that is regarded as "missing" or "not applicable"; this line is optional, but highly recommended as some programs expect this line to be declared (a real number).

The remainder of the file lists the raster values for each cell, starting at the upper-left corner. These (with optional decimal point, if needed) and are using a single .