fixed test and coherence on tolerance used by avoidSingularCovariance

src/feature_base.cpp

@@ -144,8 +144,8 @@ void FeatureBase::avoidSingularCovariance()
     if (eigensolver.info() == Eigen::Success)
     {
         // All eigenvalues must be >= 0:
-        Scalar epsilon = Constants::EPS;
-        while ((eigensolver.eigenvalues().array() < Constants::EPS).any())
+        Scalar epsilon = Constants::EPS_SMALL;
+        while ((eigensolver.eigenvalues().array() < Constants::EPS_SMALL).any())
         {
             std::cout << "----- any negative eigenvalue or too close to zero\n";
             std::cout << "previous eigenvalues: " << eigensolver.eigenvalues().transpose() << std::endl;

src/test/gtest_processor_frame_nearest_neighbor_filter_2D.cpp

@@ -111,7 +111,7 @@ TEST(ProcessorFrameNearestNeighborFilter, PointInEllipseRotated)
                                 0.0, 5.0;
 
   Eigen::Matrix1s orientation_covariance_matrix;
-  orientation_covariance_matrix << 0.0;
+  orientation_covariance_matrix << 0.01;
 
   Eigen::Vector2s tt_covariance_matrix;
   tt_covariance_matrix << 0.0, 0.0;