diff --git a/gtsam/discrete/DiscreteFactor.h b/gtsam/discrete/DiscreteFactor.h
index e24dfdf2a..f8b3fc0bb 100644
--- a/gtsam/discrete/DiscreteFactor.h
+++ b/gtsam/discrete/DiscreteFactor.h
@@ -74,13 +74,14 @@ public:
   /// @name Testable
   /// @{
 
-  // equals
+  /// equals
   virtual bool equals(const DiscreteFactor& lf, double tol = 1e-9) const = 0;
 
-  // print
-  virtual void print(const std::string& s = "DiscreteFactor\n",
-      const KeyFormatter& formatter = DefaultKeyFormatter) const {
-    Factor::print(s, formatter);
+  /// print
+  virtual void print(
+      const std::string& s = "DiscreteFactor\n",
+      const KeyFormatter& formatter = DefaultKeyFormatter) const override {
+    Base::print(s, formatter);
   }
 
   /** Test whether the factor is empty */
diff --git a/gtsam/discrete/DiscreteFactorGraph.h b/gtsam/discrete/DiscreteFactorGraph.h
index 4c2607f1f..8df602af5 100644
--- a/gtsam/discrete/DiscreteFactorGraph.h
+++ b/gtsam/discrete/DiscreteFactorGraph.h
@@ -129,8 +129,9 @@ public:
   double operator()(const DiscreteFactor::Values & values) const;
 
   /// print
-  void print(const std::string& s = "DiscreteFactorGraph",
-      const KeyFormatter& formatter =DefaultKeyFormatter) const;
+  void print(
+      const std::string& s = "DiscreteFactorGraph",
+      const KeyFormatter& formatter = DefaultKeyFormatter) const override;
 
   /** Solve the factor graph by performing variable elimination in COLAMD order using
    *  the dense elimination function specified in \c function,
diff --git a/gtsam/geometry/CalibratedCamera.h b/gtsam/geometry/CalibratedCamera.h
index eff747eb5..97ebe8c7e 100644
--- a/gtsam/geometry/CalibratedCamera.h
+++ b/gtsam/geometry/CalibratedCamera.h
@@ -144,7 +144,7 @@ public:
   bool equals(const PinholeBase &camera, double tol = 1e-9) const;
 
   /// print
-  void print(const std::string& s = "PinholeBase") const;
+  virtual void print(const std::string& s = "PinholeBase") const;
 
   /// @}
   /// @name Standard Interface
@@ -324,6 +324,11 @@ public:
   /// Return canonical coordinate
   Vector localCoordinates(const CalibratedCamera& T2) const;
 
+  /// print
+  void print(const std::string& s = "CalibratedCamera") const override {
+    PinholeBase::print(s);
+  }
+
   /// @deprecated
   inline size_t dim() const {
     return dimension;
diff --git a/gtsam/geometry/PinholeCamera.h b/gtsam/geometry/PinholeCamera.h
index ecff766e2..8ac67a5c3 100644
--- a/gtsam/geometry/PinholeCamera.h
+++ b/gtsam/geometry/PinholeCamera.h
@@ -148,7 +148,7 @@ public:
   }
 
   /// print
-  void print(const std::string& s = "PinholeCamera") const {
+  void print(const std::string& s = "PinholeCamera") const override {
     Base::print(s);
     K_.print(s + ".calibration");
   }
diff --git a/gtsam/geometry/PinholePose.h b/gtsam/geometry/PinholePose.h
index 1b5a06609..949caaa27 100644
--- a/gtsam/geometry/PinholePose.h
+++ b/gtsam/geometry/PinholePose.h
@@ -340,7 +340,7 @@ public:
   }
 
   /// print
-  void print(const std::string& s = "PinholePose") const {
+  void print(const std::string& s = "PinholePose") const override {
     Base::print(s);
     if (!K_)
       std::cout << "s No calibration given" << std::endl;
diff --git a/gtsam/gtsam.i b/gtsam/gtsam.i
index 33e9a58ca..c5bf6511c 100644
--- a/gtsam/gtsam.i
+++ b/gtsam/gtsam.i
@@ -986,7 +986,7 @@ class CalibratedCamera {
   static gtsam::CalibratedCamera Level(const gtsam::Pose2& pose2, double height);
 
   // Testable
-  void print(string s = "") const;
+  void print(string s = "CalibratedCamera") const;
   bool equals(const gtsam::CalibratedCamera& camera, double tol) const;
 
   // Manifold
@@ -1163,8 +1163,9 @@ virtual class SymbolicFactor {
 
   // From Factor
   size_t size() const;
-  void print(string s = "", const gtsam::KeyFormatter& keyFormatter =
-                                gtsam::DefaultKeyFormatter) const;
+  void print(string s = "SymbolicFactor",
+             const gtsam::KeyFormatter& keyFormatter =
+                 gtsam::DefaultKeyFormatter) const;
   bool equals(const gtsam::SymbolicFactor& other, double tol) const;
   gtsam::KeyVector keys();
 };
@@ -1177,8 +1178,9 @@ virtual class SymbolicFactorGraph {
 
   // From FactorGraph
   void push_back(gtsam::SymbolicFactor* factor);
-  void print(string s = "", const gtsam::KeyFormatter& keyFormatter =
-                                gtsam::DefaultKeyFormatter) const;
+  void print(string s = "SymbolicFactorGraph",
+             const gtsam::KeyFormatter& keyFormatter =
+                 gtsam::DefaultKeyFormatter) const;
   bool equals(const gtsam::SymbolicFactorGraph& rhs, double tol) const;
   size_t size() const;
   bool exists(size_t idx) const;
@@ -1242,8 +1244,9 @@ class SymbolicBayesNet {
   SymbolicBayesNet();
   SymbolicBayesNet(const gtsam::SymbolicBayesNet& other);
   // Testable
-  void print(string s = "", const gtsam::KeyFormatter& keyFormatter =
-                                gtsam::DefaultKeyFormatter) const;
+  void print(string s = "SymbolicBayesNet",
+             const gtsam::KeyFormatter& keyFormatter =
+                 gtsam::DefaultKeyFormatter) const;
   bool equals(const gtsam::SymbolicBayesNet& other, double tol) const;
 
   // Standard interface
@@ -2097,8 +2100,9 @@ class NonlinearFactorGraph {
   NonlinearFactorGraph(const gtsam::NonlinearFactorGraph& graph);
 
   // FactorGraph
-  void print(string s = "", const gtsam::KeyFormatter& keyFormatter =
-                                gtsam::DefaultKeyFormatter) const;
+  void print(string s = "NonlinearFactorGraph: ",
+             const gtsam::KeyFormatter& keyFormatter =
+                 gtsam::DefaultKeyFormatter) const;
   bool equals(const gtsam::NonlinearFactorGraph& fg, double tol) const;
   size_t size() const;
   bool empty() const;
diff --git a/gtsam/inference/BayesNet-inst.h b/gtsam/inference/BayesNet-inst.h
index a3bd87887..a73762258 100644
--- a/gtsam/inference/BayesNet-inst.h
+++ b/gtsam/inference/BayesNet-inst.h
@@ -26,30 +26,30 @@
 
 namespace gtsam {
 
-  /* ************************************************************************* */
-  template<class CONDITIONAL>
-  void BayesNet<CONDITIONAL>::print(const std::string& s, const KeyFormatter& formatter) const
-  {
-    Base::print(s, formatter);
-  }
-
-  /* ************************************************************************* */
-  template<class CONDITIONAL>
-  void BayesNet<CONDITIONAL>::saveGraph(const std::string &s, const KeyFormatter& keyFormatter) const
-  {
-    std::ofstream of(s.c_str());
-    of << "digraph G{\n";
-
-    for (auto conditional: boost::adaptors::reverse(*this)) {
-      typename CONDITIONAL::Frontals frontals = conditional->frontals();
-      Key me = frontals.front();
-      typename CONDITIONAL::Parents parents = conditional->parents();
-      for(Key p: parents)
-        of << keyFormatter(p) << "->" << keyFormatter(me) << std::endl;
-    }
-
-    of << "}";
-    of.close();
-  }
-
+/* ************************************************************************* */
+template <class CONDITIONAL>
+void BayesNet<CONDITIONAL>::print(
+    const std::string& s, const KeyFormatter& formatter) const {
+  Base::print(s, formatter);
 }
+
+/* ************************************************************************* */
+template <class CONDITIONAL>
+void BayesNet<CONDITIONAL>::saveGraph(const std::string& s,
+                                      const KeyFormatter& keyFormatter) const {
+  std::ofstream of(s.c_str());
+  of << "digraph G{\n";
+
+  for (auto conditional : boost::adaptors::reverse(*this)) {
+    typename CONDITIONAL::Frontals frontals = conditional->frontals();
+    Key me = frontals.front();
+    typename CONDITIONAL::Parents parents = conditional->parents();
+    for (Key p : parents)
+      of << keyFormatter(p) << "->" << keyFormatter(me) << std::endl;
+  }
+
+  of << "}";
+  of.close();
+}
+
+}  // namespace gtsam
diff --git a/gtsam/inference/BayesNet.h b/gtsam/inference/BayesNet.h
index 0597ece98..938278d5a 100644
--- a/gtsam/inference/BayesNet.h
+++ b/gtsam/inference/BayesNet.h
@@ -57,16 +57,18 @@ namespace gtsam {
     /// @name Testable
     /// @{
 
-    /** print out graph */
-    void print(const std::string& s = "BayesNet",
-      const KeyFormatter& formatter = DefaultKeyFormatter) const;
+   /** print out graph */
+   void print(
+       const std::string& s = "BayesNet",
+       const KeyFormatter& formatter = DefaultKeyFormatter) const override;
 
-    /// @}
+   /// @}
 
-    /// @name Standard Interface
-    /// @{
+   /// @name Standard Interface
+   /// @{
 
-    void saveGraph(const std::string &s, const KeyFormatter& keyFormatter = DefaultKeyFormatter) const;
+   void saveGraph(const std::string& s,
+                  const KeyFormatter& keyFormatter = DefaultKeyFormatter) const;
   };
 
 }
diff --git a/gtsam/inference/Factor.cpp b/gtsam/inference/Factor.cpp
index 58448edbb..6fe96c777 100644
--- a/gtsam/inference/Factor.cpp
+++ b/gtsam/inference/Factor.cpp
@@ -33,8 +33,8 @@ namespace gtsam {
 
   /* ************************************************************************* */
   void Factor::printKeys(const std::string& s, const KeyFormatter& formatter) const {
-    std::cout << s << " ";
-    for(Key key: keys_) std::cout << " " << formatter(key);
+    std::cout << (s.empty() ? "" : s + " ");
+    for (Key key : keys_) std::cout << " " << formatter(key);
     std::cout << std::endl;
   }
 
diff --git a/gtsam/inference/Factor.h b/gtsam/inference/Factor.h
index 1aaaff0e4..57f95b0ea 100644
--- a/gtsam/inference/Factor.h
+++ b/gtsam/inference/Factor.h
@@ -135,10 +135,14 @@ typedef FastSet<FactorIndex> FactorIndexSet;
     /// @{
 
     /// print
-    void print(const std::string& s = "Factor", const KeyFormatter& formatter = DefaultKeyFormatter) const;
+    virtual void print(
+        const std::string& s = "Factor",
+        const KeyFormatter& formatter = DefaultKeyFormatter) const;
 
     /// print only keys
-    void printKeys(const std::string& s = "Factor", const KeyFormatter& formatter = DefaultKeyFormatter) const;
+    virtual void printKeys(
+        const std::string& s = "Factor",
+        const KeyFormatter& formatter = DefaultKeyFormatter) const;
 
   protected:
     /// check equality
diff --git a/gtsam/inference/FactorGraph-inst.h b/gtsam/inference/FactorGraph-inst.h
index df68019e1..e1c18274a 100644
--- a/gtsam/inference/FactorGraph-inst.h
+++ b/gtsam/inference/FactorGraph-inst.h
@@ -37,7 +37,7 @@ namespace gtsam {
 template <class FACTOR>
 void FactorGraph<FACTOR>::print(const std::string& s,
                                 const KeyFormatter& formatter) const {
-  std::cout << s << std::endl;
+  std::cout << (s.empty() ? "" : s + " ") << std::endl;
   std::cout << "size: " << size() << std::endl;
   for (size_t i = 0; i < factors_.size(); i++) {
     std::stringstream ss;
diff --git a/gtsam/inference/FactorGraph.h b/gtsam/inference/FactorGraph.h
index 9d2308d9b..90b9d7ef2 100644
--- a/gtsam/inference/FactorGraph.h
+++ b/gtsam/inference/FactorGraph.h
@@ -285,9 +285,9 @@ class FactorGraph {
   /// @name Testable
   /// @{
 
-  /** print out graph */
-  void print(const std::string& s = "FactorGraph",
-             const KeyFormatter& formatter = DefaultKeyFormatter) const;
+  /// print out graph
+  virtual void print(const std::string& s = "FactorGraph",
+                     const KeyFormatter& formatter = DefaultKeyFormatter) const;
 
   /** Check equality */
   bool equals(const This& fg, double tol = 1e-9) const;
diff --git a/gtsam/linear/GaussianBayesNet.h b/gtsam/linear/GaussianBayesNet.h
index 06782c3cf..a45168e0b 100644
--- a/gtsam/linear/GaussianBayesNet.h
+++ b/gtsam/linear/GaussianBayesNet.h
@@ -177,6 +177,13 @@ namespace gtsam {
      */
     VectorValues backSubstituteTranspose(const VectorValues& gx) const;
 
+    /// print graph
+    virtual void print(
+        const std::string& s = "",
+        const KeyFormatter& formatter = DefaultKeyFormatter) const override {
+      Base::print(s, formatter);
+    }
+
     /**
      * @brief Save the GaussianBayesNet as an image. Requires `dot` to be
      * installed.
diff --git a/gtsam/linear/GaussianFactor.h b/gtsam/linear/GaussianFactor.h
index 9b4c5f940..72ad69693 100644
--- a/gtsam/linear/GaussianFactor.h
+++ b/gtsam/linear/GaussianFactor.h
@@ -54,8 +54,11 @@ namespace gtsam {
     virtual ~GaussianFactor() {}
 
     // Implementing Testable interface
-    virtual void print(const std::string& s = "",
-        const KeyFormatter& formatter = DefaultKeyFormatter) const = 0;
+
+    /// print
+    virtual void print(
+        const std::string& s = "",
+        const KeyFormatter& formatter = DefaultKeyFormatter) const override = 0;
 
     /** Equals for testable */
     virtual bool equals(const GaussianFactor& lf, double tol = 1e-9) const = 0;
diff --git a/gtsam/navigation/AttitudeFactor.cpp b/gtsam/navigation/AttitudeFactor.cpp
index 7f335152e..8c8eb5772 100644
--- a/gtsam/navigation/AttitudeFactor.cpp
+++ b/gtsam/navigation/AttitudeFactor.cpp
@@ -42,7 +42,8 @@ Vector AttitudeFactor::attitudeError(const Rot3& nRb,
 //***************************************************************************
 void Rot3AttitudeFactor::print(const string& s,
     const KeyFormatter& keyFormatter) const {
-  cout << s << "Rot3AttitudeFactor on " << keyFormatter(this->key()) << "\n";
+  cout << (s.empty() ? "" : s + " ") << "Rot3AttitudeFactor on "
+       << keyFormatter(this->key()) << "\n";
   nZ_.print("  measured direction in nav frame: ");
   bRef_.print("  reference direction in body frame: ");
   this->noiseModel_->print("  noise model: ");
diff --git a/gtsam/navigation/AttitudeFactor.h b/gtsam/navigation/AttitudeFactor.h
index 23fbbca89..3016b31af 100644
--- a/gtsam/navigation/AttitudeFactor.h
+++ b/gtsam/navigation/AttitudeFactor.h
@@ -114,8 +114,8 @@ public:
   }
 
   /** print */
-  void print(const std::string& s, const KeyFormatter& keyFormatter =
-      DefaultKeyFormatter) const override;
+  void print(const std::string& s = "", const KeyFormatter& keyFormatter =
+                                            DefaultKeyFormatter) const override;
 
   /** equals */
   bool equals(const NonlinearFactor& expected, double tol = 1e-9) const override;
@@ -188,8 +188,8 @@ public:
   }
 
   /** print */
-  void print(const std::string& s, const KeyFormatter& keyFormatter =
-      DefaultKeyFormatter) const override;
+  void print(const std::string& s = "", const KeyFormatter& keyFormatter =
+                                            DefaultKeyFormatter) const override;
 
   /** equals */
   bool equals(const NonlinearFactor& expected, double tol = 1e-9) const override;
diff --git a/gtsam/navigation/GPSFactor.cpp b/gtsam/navigation/GPSFactor.cpp
index f2448c488..1d6b78e13 100644
--- a/gtsam/navigation/GPSFactor.cpp
+++ b/gtsam/navigation/GPSFactor.cpp
@@ -24,7 +24,8 @@ namespace gtsam {
 
 //***************************************************************************
 void GPSFactor::print(const string& s, const KeyFormatter& keyFormatter) const {
-  cout << s << "GPSFactor on " << keyFormatter(key()) << "\n";
+  cout << (s.empty() ? "" : s + " ") << "GPSFactor on " << keyFormatter(key())
+       << "\n";
   cout << "  GPS measurement: " << nT_ << "\n";
   noiseModel_->print("  noise model: ");
 }
diff --git a/gtsam/navigation/GPSFactor.h b/gtsam/navigation/GPSFactor.h
index f6469346e..8fcf0f099 100644
--- a/gtsam/navigation/GPSFactor.h
+++ b/gtsam/navigation/GPSFactor.h
@@ -71,8 +71,8 @@ public:
   }
 
   /// print
-  void print(const std::string& s, const KeyFormatter& keyFormatter =
-      DefaultKeyFormatter) const override;
+  void print(const std::string& s = "", const KeyFormatter& keyFormatter =
+                                            DefaultKeyFormatter) const override;
 
   /// equals
   bool equals(const NonlinearFactor& expected, double tol = 1e-9) const override;
@@ -143,8 +143,8 @@ public:
   }
 
   /// print
-  void print(const std::string& s, const KeyFormatter& keyFormatter =
-      DefaultKeyFormatter) const override;
+  void print(const std::string& s = "", const KeyFormatter& keyFormatter =
+                                            DefaultKeyFormatter) const override;
 
   /// equals
   bool equals(const NonlinearFactor& expected, double tol = 1e-9) const override;
diff --git a/gtsam/nonlinear/NonlinearFactor.h b/gtsam/nonlinear/NonlinearFactor.h
index 8c257f7ca..adb6310e8 100644
--- a/gtsam/nonlinear/NonlinearFactor.h
+++ b/gtsam/nonlinear/NonlinearFactor.h
@@ -70,8 +70,9 @@ public:
   /// @{
 
   /** print */
-  virtual void print(const std::string& s = "",
-    const KeyFormatter& keyFormatter = DefaultKeyFormatter) const;
+  virtual void print(
+      const std::string& s = "",
+      const KeyFormatter& keyFormatter = DefaultKeyFormatter) const override;
 
   /** Check if two factors are equal */
   virtual bool equals(const NonlinearFactor& f, double tol = 1e-9) const;
diff --git a/gtsam/nonlinear/NonlinearFactorGraph.h b/gtsam/nonlinear/NonlinearFactorGraph.h
index 989f493d3..9bca4a29d 100644
--- a/gtsam/nonlinear/NonlinearFactorGraph.h
+++ b/gtsam/nonlinear/NonlinearFactorGraph.h
@@ -99,8 +99,9 @@ namespace gtsam {
     NonlinearFactorGraph(const FactorGraph<DERIVEDFACTOR>& graph) : Base(graph) {}
 
     /** print */
-    void print(const std::string& str = "NonlinearFactorGraph: ",
-               const KeyFormatter& keyFormatter = DefaultKeyFormatter) const;
+    void print(
+        const std::string& str = "NonlinearFactorGraph: ",
+        const KeyFormatter& keyFormatter = DefaultKeyFormatter) const override;
 
     /** print errors along with factors*/
     void printErrors(const Values& values, const std::string& str = "NonlinearFactorGraph: ",
diff --git a/gtsam/sfm/BinaryMeasurement.h b/gtsam/sfm/BinaryMeasurement.h
index 99e553f7a..7e102fee7 100644
--- a/gtsam/sfm/BinaryMeasurement.h
+++ b/gtsam/sfm/BinaryMeasurement.h
@@ -64,8 +64,8 @@ private:
   /// @name Testable
   /// @{
 
-  void print(const std::string &s,
-             const KeyFormatter &keyFormatter = DefaultKeyFormatter) const {
+  void print(const std::string &s, const KeyFormatter &keyFormatter =
+                                       DefaultKeyFormatter) const override {
     std::cout << s << "BinaryMeasurement(" << keyFormatter(this->key1()) << ","
               << keyFormatter(this->key2()) << ")\n";
     traits<T>::Print(measured_, "  measured: ");
diff --git a/gtsam/symbolic/SymbolicBayesNet.h b/gtsam/symbolic/SymbolicBayesNet.h
index ca87b2bbc..45df56abd 100644
--- a/gtsam/symbolic/SymbolicBayesNet.h
+++ b/gtsam/symbolic/SymbolicBayesNet.h
@@ -63,6 +63,13 @@ namespace gtsam {
     /** Check equality */
     GTSAM_EXPORT bool equals(const This& bn, double tol = 1e-9) const;
 
+    /// print
+    GTSAM_EXPORT void print(
+        const std::string& s = "SymbolicBayesNet",
+        const KeyFormatter& formatter = DefaultKeyFormatter) const override {
+      Base::print(s, formatter);
+    }
+
     /// @}
 
     /// @name Standard Interface
diff --git a/gtsam/symbolic/SymbolicConditional.cpp b/gtsam/symbolic/SymbolicConditional.cpp
index d733c0937..f0d9944b2 100644
--- a/gtsam/symbolic/SymbolicConditional.cpp
+++ b/gtsam/symbolic/SymbolicConditional.cpp
@@ -20,18 +20,17 @@
 
 namespace gtsam {
 
-  using namespace std;
-
-  /* ************************************************************************* */
-  void SymbolicConditional::print(const std::string& str, const KeyFormatter& keyFormatter) const
-  {
-    BaseConditional::print(str, keyFormatter);
-  }
-
-  /* ************************************************************************* */
-  bool SymbolicConditional::equals(const This& c, double tol) const
-  {
-    return BaseFactor::equals(c) && BaseConditional::equals(c);
-  }
+using namespace std;
 
+/* ************************************************************************* */
+void SymbolicConditional::print(const std::string& str,
+                                const KeyFormatter& keyFormatter) const {
+  BaseConditional::print(str, keyFormatter);
 }
+
+/* ************************************************************************* */
+bool SymbolicConditional::equals(const This& c, double tol) const {
+  return BaseFactor::equals(c) && BaseConditional::equals(c);
+}
+
+}  // namespace gtsam
diff --git a/gtsam/symbolic/SymbolicConditional.h b/gtsam/symbolic/SymbolicConditional.h
index ead72a989..4088cbfb6 100644
--- a/gtsam/symbolic/SymbolicConditional.h
+++ b/gtsam/symbolic/SymbolicConditional.h
@@ -105,7 +105,9 @@ namespace gtsam {
     /// @name Testable
 
     /** Print with optional formatter */
-    virtual void print(const std::string& str = "", const KeyFormatter& keyFormatter = DefaultKeyFormatter) const;
+    virtual void print(
+        const std::string& str = "",
+        const KeyFormatter& keyFormatter = DefaultKeyFormatter) const override;
 
     /** Check equality */
     bool equals(const This& c, double tol = 1e-9) const;
diff --git a/gtsam/symbolic/SymbolicFactor.h b/gtsam/symbolic/SymbolicFactor.h
index 66657aa7d..2a488a4da 100644
--- a/gtsam/symbolic/SymbolicFactor.h
+++ b/gtsam/symbolic/SymbolicFactor.h
@@ -92,6 +92,20 @@ namespace gtsam {
 
     bool equals(const This& other, double tol = 1e-9) const;
 
+    /// print
+    void print(
+        const std::string& s = "SymbolicFactor",
+        const KeyFormatter& formatter = DefaultKeyFormatter) const override {
+      Base::print(s, formatter);
+    }
+
+    /// print only keys
+    void printKeys(
+        const std::string& s = "SymbolicFactor",
+        const KeyFormatter& formatter = DefaultKeyFormatter) const override {
+      Base::printKeys(s, formatter);
+    }
+
     /// @}
 
     /// @name Advanced Constructors
diff --git a/gtsam/symbolic/SymbolicFactorGraph.h b/gtsam/symbolic/SymbolicFactorGraph.h
index b6f0de2ae..7f4c84631 100644
--- a/gtsam/symbolic/SymbolicFactorGraph.h
+++ b/gtsam/symbolic/SymbolicFactorGraph.h
@@ -88,6 +88,13 @@ namespace gtsam {
 
     bool equals(const This& fg, double tol = 1e-9) const;
 
+    /// print
+    void print(
+        const std::string& s = "SymbolicFactorGraph",
+        const KeyFormatter& formatter = DefaultKeyFormatter) const override {
+      Base::print(s, formatter);
+    }
+
     /// @}
 
     /// @name Standard Interface
diff --git a/gtsam_unstable/linear/InequalityFactorGraph.h b/gtsam_unstable/linear/InequalityFactorGraph.h
index d042b0436..7016a7e97 100644
--- a/gtsam_unstable/linear/InequalityFactorGraph.h
+++ b/gtsam_unstable/linear/InequalityFactorGraph.h
@@ -37,8 +37,9 @@ public:
   typedef boost::shared_ptr<InequalityFactorGraph> shared_ptr;
 
   /** print */
-  void print(const std::string& str, const KeyFormatter& keyFormatter =
-      DefaultKeyFormatter) const {
+  void print(
+      const std::string& str = "",
+      const KeyFormatter& keyFormatter = DefaultKeyFormatter) const override {
     Base::print(str, keyFormatter);
   }