1. A system for displaying structure of a source computer program comprising: a) an output display; b) graph analysis means for analyzing said source computer program, said graph analysis means comprising: i) analysis means for transforming said source computer program into a directed graph file comprising a function list file and a function call list file, said function list file comprising one or more nodes, said function call list file comprising one or more arcs; ii) hierarchical graph analysis (HGA) means for transforming said directed graph file into an HGA directed graph file; iii) display means for displaying said HGA directed graph file on said output display.