From 6d4c101d860d7643e0ee972d4dfef510c125f956 Mon Sep 17 00:00:00 2001
From: Richard Roberts <richard.jw.roberts@gmail.com>
Date: Fri, 16 Aug 2013 04:09:48 +0000
Subject: [PATCH] Fixed empty list bug in COLAMDConstrainFirst

---
 gtsam/inference/Ordering.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gtsam/inference/Ordering.cpp b/gtsam/inference/Ordering.cpp
index b0ac9669f..4f4b14bb5 100644
--- a/gtsam/inference/Ordering.cpp
+++ b/gtsam/inference/Ordering.cpp
@@ -163,7 +163,7 @@ namespace gtsam {
         ++ group;
     }
 
-    if(!forceOrder)
+    if(!forceOrder && !constrainFirst.empty())
       ++ group;
     BOOST_FOREACH(int& c, cmember)
       if(c == none)