[Yt-svn] yt-commit r1714 - trunk/yt/extensions

[sskory at wrangler.dreamhost.com]

Author: sskory
Date: Sat May  1 09:19:02 2010
New Revision: 1714
URL: http://yt.enzotools.org/changeset/1714

Log:
Prevent divide by zero when there is exactly one halo in a snapshot.

Modified:
   trunk/yt/extensions/MergerTree.py

Modified: trunk/yt/extensions/MergerTree.py
==============================================================================
--- trunk/yt/extensions/MergerTree.py	(original)
+++ trunk/yt/extensions/MergerTree.py	Sat May  1 09:19:02 2010
@@ -791,7 +791,7 @@
             self.cursor.execute(line, value)
             result = self.cursor.fetchone()
             self.nodes[halo] = Node(na.array([result[2],result[3],result[4]]),
-                result[1], [], result[0], 1. - float(result[5])/maxID)
+                result[1], [], result[0], 1. - float(result[5])/(maxID+1)) #+1 to prevent /0
             self.levels[result[0]].append(halo)
 
     def _open_dot(self, dotfile):