In GIS it is necessary to optimize the analysis function of the shortest path as the hinge of spatial network analysis

which includes shortest path analysis

resource allocation and isochrone

and so on. Here derived from the traditional calculating method

i.e. Dijkstra algorithm

the analysis procedure of the shortest path is improved by adopting the data structure of binary heap to complete the operation of priority queue. Initialization

Extraction

and Relzxztion. The topological structure of geographical network data and the detailed implementing steps of the shortest path are also discussed. Furthermore

the visualizing calculation of the shortest path is completed by COM(Component Object Model) techniques

and the calculating procedure is encapsulated into the component of the geographic network class. The complexity analysis and the case of this algorithm showes that the modified algorithm is applicable to improve the efficiency of spatial analysis of the net system.