Figure 1

Determination of interaction weights according to graph distances. An evaluation scheme of the weight matrix corresponds to a style of layout. Three styles are shown here: 1) the common style, where weights are set to roughly balance the attractive and repulsive interactions, consequently nodes are placed relatively even in the layout area while modules are separated clearly; 2) the compact style, where attractive interactions are dominant, so nodes are located closely in a tight space, some modules may be not well separated; 3) the stretched style, where attractions are relatively weak, which makes modules distribute far from each other.