diff --git a/gtsam/geometry/Cal3.cpp b/gtsam/geometry/Cal3.cpp
index 240d01e12..31e9bf834 100644
--- a/gtsam/geometry/Cal3.cpp
+++ b/gtsam/geometry/Cal3.cpp
@@ -62,11 +62,11 @@ void Cal3::print(const std::string& s) const { gtsam::print((Matrix)K(), s); }
 
 /* ************************************************************************* */
 bool Cal3::equals(const Cal3& K, double tol) const {
-  return (std::abs(fx_ - K.fx_) < tol) && (std::abs(fy_ - K.fy_) < tol) &&
-         (std::abs(s_ - K.s_) < tol) && (std::abs(u0_ - K.u0_) < tol) &&
-         (std::abs(v0_ - K.v0_) < tol);
+  return (std::fabs(fx_ - K.fx_) < tol) && (std::fabs(fy_ - K.fy_) < tol) &&
+         (std::fabs(s_ - K.s_) < tol) && (std::fabs(u0_ - K.u0_) < tol) &&
+         (std::fabs(v0_ - K.v0_) < tol);
 }
 
 /* ************************************************************************* */
 
-}  // namespace gtsam
+}  // \ namespace gtsam
diff --git a/gtsam/geometry/Cal3.h b/gtsam/geometry/Cal3.h
index 13cd4de69..7384fe958 100644
--- a/gtsam/geometry/Cal3.h
+++ b/gtsam/geometry/Cal3.h
@@ -68,7 +68,7 @@ void calibrateJacobians(const Cal& calibration, const Point2& pn,
  */
 class GTSAM_EXPORT Cal3 {
  protected:
-  double fx_, fy_, s_, u0_, v0_;
+  double fx_, fy_, s_, u0_, v0_;  ///< focal length, skew and principal point
 
  public:
   enum { dimension = 5 };
@@ -113,7 +113,7 @@ class GTSAM_EXPORT Cal3 {
                                                const Cal3& cal);
 
   /// print with optional string
-  virtual void print(const std::string& s = "Cal3") const;
+  virtual void print(const std::string& s = "") const;
 
   /// Check if equal up to specified tolerance
   bool equals(const Cal3& K, double tol = 10e-9) const;
diff --git a/gtsam/geometry/Cal3DS2.h b/gtsam/geometry/Cal3DS2.h
index fe08fc5fb..58ccae04f 100644
--- a/gtsam/geometry/Cal3DS2.h
+++ b/gtsam/geometry/Cal3DS2.h
@@ -32,7 +32,7 @@ namespace gtsam {
  */
 class GTSAM_EXPORT Cal3DS2 : public Cal3DS2_Base {
 
-  typedef Cal3DS2_Base Base;
+  using Base = Cal3DS2_Base;
 
 public:
 
diff --git a/gtsam/geometry/Cal3DS2_Base.h b/gtsam/geometry/Cal3DS2_Base.h
index 536fb1161..0c6a4a3cd 100644
--- a/gtsam/geometry/Cal3DS2_Base.h
+++ b/gtsam/geometry/Cal3DS2_Base.h
@@ -41,9 +41,9 @@ namespace gtsam {
  */
 class GTSAM_EXPORT Cal3DS2_Base : public Cal3 {
  protected:
-  double k1_, k2_;     // radial 2nd-order and 4th-order
-  double p1_, p2_;     // tangential distortion
-  double tol_ = 1e-5;  // tolerance value when calibrating
+  double k1_, k2_;     ///< radial 2nd-order and 4th-order
+  double p1_, p2_;     ///< tangential distortion
+  double tol_ = 1e-5;  ///< tolerance value when calibrating
 
  public:
   enum { dimension = 9 };
diff --git a/gtsam/geometry/Cal3Unified.h b/gtsam/geometry/Cal3Unified.h
index 6fc37b0d1..7a0931ff5 100644
--- a/gtsam/geometry/Cal3Unified.h
+++ b/gtsam/geometry/Cal3Unified.h
@@ -47,7 +47,7 @@ class GTSAM_EXPORT Cal3Unified : public Cal3DS2_Base {
 
 private:
 
-  double xi_;  // mirror parameter
+  double xi_;  ///< mirror parameter
 
 public:
 
diff --git a/gtsam/geometry/Cal3_S2Stereo.cpp b/gtsam/geometry/Cal3_S2Stereo.cpp
index b4e70202e..43f0fb12f 100644
--- a/gtsam/geometry/Cal3_S2Stereo.cpp
+++ b/gtsam/geometry/Cal3_S2Stereo.cpp
@@ -32,7 +32,7 @@ void Cal3_S2Stereo::print(const std::string& s) const {
 /* ************************************************************************* */
 bool Cal3_S2Stereo::equals(const Cal3_S2Stereo& other, double tol) const {
   const Cal3_S2* base = dynamic_cast<const Cal3_S2*>(&other);
-  return Cal3_S2::equals(*base, tol) && (std::abs(b_ - other.baseline()) < tol);
+  return Cal3_S2::equals(*base, tol) && (std::fabs(b_ - other.baseline()) < tol);
 }
 
 /* ************************************************************************* */