Technique for drawing directed graphs
US4953106A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 23, 1989 |
| Grant date | Aug 28, 1990 |
| Priority date | — |
| Expiry date | May 23, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T11/206
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a computer-implemented technique for drawing directed graphs providing reduced crossings and improved picture quality. An edge list description provided by a user is processed to produce a ranking of all nodes that minimizes the weighted sum of all edges, an edge cost being the product of its weight and length. Nodes within a ranking are then positioned to reduce edge crossings using a heuristic based on node positions in adjacent ranks. Such heuristic uses a generalized median as a weighting function plus node transposition to avoid senseless edge crossings before proceeding to a next rank. Nodes are then positioned to minimize the weighted sum of horizontal distances among connected nodes. Spline control points are then computed for interconnected nodes, and a code sequence for a drawing is generated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.