Based on the data-independent assessment of digital elevation model(DEM),a quantitative analysis and comparison of five routing algorithm including D8,Rho8,FMFD,Dinf and DEMON,which are widely applied in GIS software and hydrological model is presented.
At the same time,in view of the problem of the program error occurrence with the changed path of database file,it expounds in detail the dynamic path method for establishing the connection between Visual Basic application program and Access database,resolves the static problem in the connection,and it can find out correctly the database files under the condition of the database .
From the point of view of linking the dynamic paths,the algorithms about the net-node value, the net- layer value and the linking statements are studied.
On the basis of analyzing the classic arithmetic on the template matching,three new methods,format single path searching arithmetic,format converse embranchment arithmetic and dynamic path matching arithmetic are proposed.