Constrained Stress Majorization Using Diagonally Scaled Gradient Projection
- Cite this paper as:
- Dwyer T., Marriott K. (2008) Constrained Stress Majorization Using Diagonally Scaled Gradient Projection. In: Hong SH., Nishizeki T., Quan W. (eds) Graph Drawing. GD 2007. Lecture Notes in Computer Science, vol 4875. Springer, Berlin, Heidelberg
Constrained stress majorization is a promising new technique for integrating application specific layout constraints into force-directed graph layout. We significantly improve the speed and convergence properties of the constrained stress-majorization technique for graph layout by employing a diagonal scaling of the stress function. Diagonal scaling requires the active-set quadratic programming solver used in the projection step to be extended to handle separation constraints with scaled variables, i.e. of the form siyi + gij ≤ sjyj. The changes, although relatively small, are quite subtle and explained in detail.