Method and apparatus for logical zooming of a directed graph

The present invention relates to a logical zooming method and apparatus for a directed graph in which hierarchical nodes are connected by arcs. A directed graph is logically zoomed, whereby the appearance of a node directly related to a target node can be exaggerated and the structure of an entire graph can be readily understood. A directed graph is used in which hierarchical nodes are connected by arcs. In the directed graph, a node that has a predetermined logical relationship with a selected node is displayed differently than are the other nodes. For example, a displayed node logically near the selected node is large, while a displayed node logically distant is small, or the node logically near the selected node is moved closer to the selected node.