The Research On Digital Map Optimal Path Algorithms Chosen

Dijkstra algorithms, designed by a Netherlandish mathematician E. W. Dijkstra in 1959, which is the most theoretically integrated and extensive method to solve the shortest path in digital-map area, was called the label setting algorithms. Analyzing and summarizing the idea of Dijkstra algorithms with subsequent debugging the corresponding program constituted the half part of the dissertation. It was located the shortage of Dijkstra algorithms that the lowness of searching efficiency and the highness of operating complexity, which basically was limited by computer development, on account of economizing the space occupied the most important status in historical background. Presently, hardware's capacity had expanded at very fast speed; individual did not care about the space problem. So, it is the necessary attempts that improve the Dijkstra algorithms in order to increase the searching efficiency.In the optimal path chosen area, the classic Dijkstra algorithms were the base method, which was the core of all path algorithms, different actualizing modes were utilized in diversiform system.In the rest part of this dissertation, begin with analysis of two kinds of optimal route, target arrangement and limit the searching area, and then summarized the two complied principle of building new mathematic mode, put the point in designing and building the creative optimal modes, rectangle,sector and compositive mode, in the base of the ellipse mode."Core area"and"Blind section"were the newest concepts I defined.By the exploring and research the new algorithms, working efficiency would be bring up fast. Improved algorithms could fulfill the more and more data processing in the GIS system and be prominent in stability,operation and efficiency.