An augmented directed graph base for application development

Directed graphs have been used as the theoretical base for many applications in Computer Science -- especially artificial intelligence. Two drawbacks to the use of directed graphs for more practical work have been:1. The difficulty in associating data of a variety of types with the nodes in the graph and with the connections between the nodes, and2. The inability to search and modify the graph efficiently as the size and complexity of the graph grows.This paper describes a library of cooperating routines for dealing with directed graphs that overcomes these objections. The first problem is overcome by adding to the usual directed graph model the concepts of "data tags" and "connection descriptors." The problem of efficiency is addressed by using a binary tree facility to implement the augmented directed graph. This paper describes the augmented directed graph "access method" and how it can be used as the base for application development.