在VFP6.0中实现铁路路网里程计算

Railway Network Route Length Calculation Program with Visual FoxPro 6.0 Program Software

概述了Dijkstra关于铁路路网里程计算的基本原理与算法。详细介绍了应用VisualFoxPro 6 0编程软件编制路网里程计算程序的设计原理、系统构成、数据结构等基本思路。定义了铁路运输网络中的点 (车站 )、基点、普通点、基线等概念 ,提出了通过生成二维数组基点里程表 ,直接调用任意两基点间最短路径里程 ,最终实现路网里程计算的设计思想。并以此为基础 ,对基点与基点、基点与普通点、普通点与普通点 ,同条基线上的两个普通点间如何计算最短路径里程 ,进行了详细的论述与论证。还针对旅客列车行车路线中出现的特殊经由里程计算问题 ,提出经由站—对称点 (车站 )算法。阐述了该算法成立的条件 ,并对经由站。

The paper describes the basic principle and the Dijkstra algorithm concerning the calculation of the railway network route length. With visual FoxPro 6 0 program software, it details the design rationale of the calculation programming of the railway network route length, and the clues of the configuration and data structure. The concepts are defined of how to calculate the shortest route length between point (station) and base point, ordinarily point and baseline. The paper proposes to build a two dimensional array base point mileage table, making it possible to access any shortest route between two base points and realize the mission of network route length calculation. On this basis, it is particularly discussed about how to calculate the beeline route length between one base point and another, one base point and one ordinary point, between two ordinary points, and between two ordinary points on the same baseline. The paper also briefs on a special algorithm of a train between a through station and a symmetrical station to address the problem of special routes. It details the conditions of this algorithm, and discusses the rationale and method of selecting the through station and the symmetrical station on the shortest route.