diff --git a/cpp/Rot3.cpp b/cpp/Rot3.cpp
index 166b550b0..c72621538 100644
--- a/cpp/Rot3.cpp
+++ b/cpp/Rot3.cpp
@@ -113,7 +113,8 @@ namespace gtsam {
   // Log map at identity - return the canonical coordinates of this rotation
   inline Vector logmap(const Rot3& R) {
     double tr = R.r1().x()+R.r2().y()+R.r3().z();
-    if (tr==3.0)         // when theta = 0, +-2pi, +-4pi, etc.
+    if (fabs(tr-3.0) < 1e-10)   // when theta = 0, +-2pi, +-4pi, etc.
+//    if (tr == 3.0)   // when theta = 0, +-2pi, +-4pi, etc.
       return zero(3);
     else if (tr==-1.0) { // when theta = +-pi, +-3pi, +-5pi, etc.
       if(R.r3().z() != -1.0)