A Research On Raster Based GIS Spatial Analysis Arithmetic And Its Programme Practice

GIS (Geography Information System) is a new hotspot of IT. It is widely used in many aspects such as resource and environment management. The function of a GIS system is closely related to the GIS software it uses. There is a wide difference of the spatial analysis functions among the popular used GIS software. Some widely used GIS software, such as ArcGIS, is powerful in spatial analysis. But its high price, complicated operation, costly system maintenance fee made it a barrier for these software to be widely usedIn this article ,the spatial analysis methods and spatial modeling methods are studied, and the application area, difference and c orrelation between these methods are analyzed. With the usage of object orient programming, GIS software RasterTools is developed. This software uses pure text file as its data format. Its function is limited to spatial analysis and is easy to use. But for its integrated spatial analysis functions, users can expand its function by means of self written spatial analysis script.Also in this article, ComGIS technology is studied. As a result of the application of these technology, GIS control RasterToolsObj is developed. This control give an access for the system developer to adding GIS functions into their system, just as the functions RasterTools can do. The two software, RasterTools and RasterToolsObj, made it possible for the users to manipulate raster data on different levels. And it is valuable in many areas such as coupling with traditional MIS, embed development, expandability, operation complexity, reducing system costs etc.At the end, the application future is talked about and an application system is developed. In these application it is proved that RasterTools and RsterToolsObj software are all powerful in raster data manipulation, and can do complicated spatial analysis. With the merit of script running, it can meet almost all demands of raster based GIS system.With the development of computer software and hardware, raster data will run a more important role in GIS project. RasterTools and RasterToolsObj software is cheap and powerful, and is a shortcut for GIS system development.