node.asy is not only easy to use, but also with great extensibility. can draw graph theory, automata, flowchart, circuit-like graphics
Note: v5.0 is not compatible with v4.0, with the new layout syntax replacing the old dock syntax
Scientific Publication:
The usage of this library is described here, or you can just view the source codes of samples to figure out what they mean, they are quite self-explanatory!
Draw graph theory graph using adj matrix syntax
https://github.com/taoari/asy-graphtheory
Google Code:
http://code.google.com/p/asy-graphtheory
CTEX:
http://bbs.ctex.org/viewthread.php?tid=70055&extra=page%3D1
http://bbs.ctex.org/viewthread.php?tid=69922&extra=page%3D1
SourceForge.net:
https://sourceforge.net/projects/asymptote/forums/forum/409349/topic/4923334/index/page/1