Number: 77 Title: Problems with -x flag to neato Submitter: Emden Gansner Date: Jan 21 2002 Subsys: neato Version: 1.1.16 System: *-*-* Severity: minor Problem:
The following file causes neato to core dump. In general,
I believe the -x option is not doing what is intended. As
currently implemented, it checks one node at a time and if
the node is a leaf, it deletes the longest chain starting at the
leaf. As this process introduces new leaves, it has the potential
of deleting the entire graph if it is a forest.
Input:
graph S {
1 -- 6;
2 -- 3 -- 6;
4 -- 5 -- 6;
}
Fix:
[erg] The fix adopts the implied original semantics, essentially
pruning any trees, with every node in the resulting graph having
degree > 1. The fix does handle loops and multiedges, basically
ignoring loops and multiedges in the topology. It would be good
to provide other options, e.g., pruning 1 level of chains or keeping
loops and multiedges in the degree count, but the might better be
provided by an external tool such as gpr. Of course, one could make
the same claim for this option.
Owner: erg Status: Fixed (23 March 2002)