From e8a2d1f6d5a73094b489c294d3bfe16692905af6 Mon Sep 17 00:00:00 2001
From: "Gustavo J. A. M. Carneiro" <gjc@inescporto.pt>
Date: Tue, 10 May 2011 14:42:20 +0100
Subject: [PATCH] pyviz: autoscale_view does nothing if there are no nodes

---
 src/visualizer/visualizer/core.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/visualizer/visualizer/core.py b/src/visualizer/visualizer/core.py
index 9ab7367cc..63a91444f 100644
--- a/src/visualizer/visualizer/core.py
+++ b/src/visualizer/visualizer/core.py
@@ -1126,6 +1126,8 @@ class Visualizer(gobject.GObject):
         __IPYTHON__.runcode = types.MethodType(runcode, __IPYTHON__)                
 
     def autoscale_view(self):
+        if not self.nodes:
+            return
         self._update_node_positions()
         positions = [node.get_position() for node in self.nodes.itervalues()]
         min_x, min_y = min(x for (x,y) in positions), min(y for (x,y) in positions)