diff --git a/gtsam/discrete/DecisionTreeFactor.cpp b/gtsam/discrete/DecisionTreeFactor.cpp
index ad4cbad43..9de750f2e 100644
--- a/gtsam/discrete/DecisionTreeFactor.cpp
+++ b/gtsam/discrete/DecisionTreeFactor.cpp
@@ -22,6 +22,7 @@
 #include <gtsam/base/FastSet.h>
 
 #include <boost/make_shared.hpp>
+#include <boost/format.hpp>
 #include <utility>
 
 using namespace std;
@@ -65,9 +66,13 @@ namespace gtsam {
 
   /* ************************************************************************* */
   void DecisionTreeFactor::print(const string& s,
-      const KeyFormatter& formatter) const {
+                                 const KeyFormatter& formatter) const {
     cout << s;
-    ADT::print("Potentials:",formatter);
+    cout << " f[";
+    for (auto&& key : keys())
+      cout << boost::format(" (%1%,%2%),") % formatter(key) % cardinality(key);
+    cout << " ]" << endl;
+    ADT::print("Potentials:", formatter);
   }
 
   /* ************************************************************************* */
diff --git a/gtsam/discrete/DecisionTreeFactor.h b/gtsam/discrete/DecisionTreeFactor.h
index 8beeb4c4a..251575739 100644
--- a/gtsam/discrete/DecisionTreeFactor.h
+++ b/gtsam/discrete/DecisionTreeFactor.h
@@ -127,11 +127,16 @@ namespace gtsam {
       return combine(keys, ADT::Ring::add);
     }
 
-    /// Create new factor by maximizing over all values with the same separator values
+    /// Create new factor by maximizing over all values with the same separator.
     shared_ptr max(size_t nrFrontals) const {
       return combine(nrFrontals, ADT::Ring::max);
     }
 
+    /// Create new factor by maximizing over all values with the same separator.
+    shared_ptr max(const Ordering& keys) const {
+      return combine(keys, ADT::Ring::max);
+    }
+
     /// @}
     /// @name Advanced Interface
     /// @{