prog/lib to draw graphs

[Kyle Rawlins]

On Jan 22, 2004, at 5:15 AM, Florian Lindner wrote:
> Thanks! (to all)
> Does GraphViz also support the automated optimal placement of nodes? 
> I'll
> have many nodes...

What constitutes optimal is a matter of an entire subfield of graph 
theory, and is pretty different depending on what type of graph you are 
doing.  Nonetheless, graphviz does pretty well without any cues.  In a 
project I used to use it in (a browser for large automatically learned 
ontologies) I would sometimes use it to render thousands of nodes, and 
it would usually look better than I expected.  There is a problem in 
that highly connected large graphs result in a lot of black ink for the 
edges, since in such graph they will be much denser than the DPI of 
your screen.  I'm not sure you'll find any full display of a large 
graph practical for interactive use without a lot of tweaking.

If you do want to use it interactively, be prepared for long waits 
(>30s, sometimes several minutes) for very large graphs.  For small 
graphs, it's near instantaneous.  This is a problem with graph layout 
algorithms in general, however, and not graphviz per se - they do not 
scale very efficiently.  People I know who used ygraph, a commercial 
package, told me that it was not much faster on large graphs.

hope that helps,
-kyle