Miscellaneous refactoring

Author: keevindoherty

include/octree.h

@@ -18,7 +18,7 @@ namespace la3dm {
     void hash_key_to_node(OcTreeHashKey key, unsigned short &depth, unsigned short &index);
 
     /*
-     * @brief A simple OcTree to organize GP occupancy data in one block.
+     * @brief A simple OcTree to organize occupancy data in one block.
      *
      * OcTree doesn't store positions of nodes in order to reduce memory usage.
      * The nodes in OcTrees are indexed by OcTreeHashKey which can be used to

include/octree_node.h

@@ -12,10 +12,10 @@ namespace la3dm {
     };
 
     /*
-     * @brief GP regression ouputs and occupancy state.
+     * @brief Inference ouputs and occupancy state.
      *
-     * Occupancy has member variables: m_ivar (m*ivar), ivar (1/var) and State.
-     * This representation speeds up the updates via BCM.
+     * Occupancy has member variables: m_A and m_B (kernel densities of positive
+     * and negative class, respectively) and State.
      * Before using this class, set the static member variables first.
      */
     class Occupancy {
@@ -47,9 +47,9 @@ namespace la3dm {
         ~Occupancy() { }
 
         /*
-         * @brief Bayesian Committee Machine (BCM) update for Gaussian Process regression.
-         * @param new_m mean resulted from GP regression
-         * @param new_var variance resulted from GP regression
+         * @brief Exact updates for nonparametric Bayesian kernel inference
+         * @param ybar kernel density estimate of positive class (occupied)
+         * @param kbar kernel density of negative class (unoccupied)
          */
         void update(float ybar, float kbar);
 
@@ -76,23 +76,15 @@ namespace la3dm {
         bool classified;
 
     private:
-        // float m;  // m / var or m * ivar
-        // float var;    // 1.0 / var
         float m_A;
         float m_B;
         State state;
 
-        static float sf2;   // signal variance
+        static float sf2;
         static float ell;   // length-scale
-        // static float noise; // noise variance
-        // static float l;     // gamma in logistic functions
 
-        // static float max_ivar; // minimum variance
-        // static float min_ivar; // maximum variance
-        // static float min_known_ivar;  // maximum variance for nodes to be considered as FREE or OCCUPIED
-
-        static float prior_A;
-        static float prior_B;
+        static float prior_A; // prior on alpha
+        static float prior_B; // prior on beta
 
         static float free_thresh;     // FREE occupancy threshold
         static float occupied_thresh; // OCCUPIED occupancy threshold
@@ -102,4 +94,4 @@ namespace la3dm {
     typedef Occupancy OcTreeNode;
 }
 
-#endif //GPOCTOMAP_OCCUPANCY_H
+#endif // LA3DM_OCCUPANCY_H

src/octree_node.cpp

@@ -1,30 +1,20 @@
 #include "octree_node.h"
-// #include "gpregressor.h"
 #include <cmath>
 
 namespace la3dm {
 
     /// Default static values
     float Occupancy::sf2 = 1.0f;
     float Occupancy::ell = 1.0f;
-    // float Occupancy::noise = 0.01f;
-    // float Occupancy::l = 100.f;
-
-    // float Occupancy::max_ivar = 1000.0f;
-    // float Occupancy::min_ivar = 0.001f;
-
-    // float Occupancy::min_known_ivar = 10.0f;
     float Occupancy::free_thresh = 0.3f;
     float Occupancy::occupied_thresh = 0.7f;
+    float Occupancy::var_thresh = 1000.0f;
     float Occupancy::prior_A = 0.5f;
     float Occupancy::prior_B = 0.5f;
-    float Occupancy::var_thresh = 1000.0f;
-
 
     Occupancy::Occupancy(float A, float B) : m_A(Occupancy::prior_A + A), m_B(Occupancy::prior_B + B) {
         classified = false;
         float var = get_var();
-        // std::cout << var << std::endl;
         if (var > Occupancy::var_thresh)
             state = State::UNKNOWN;
         else {
@@ -35,33 +25,19 @@ namespace la3dm {
     }
 
     float Occupancy::get_prob() const {
-        // logistic regression function
-        // return 1.0f / (1.0f + (float) exp(-l * m_ivar / Occupancy::max_ivar));
-        // return m_ivar;
         return m_A / (m_A + m_B);
     }
 
     void Occupancy::update(float ybar, float kbar) {
-        // ivar += 1.0 / new_var - Occupancy::sf2;
-        // m_ivar += new_m / new_var;
-        // m_ivar = new_m;
         classified = true;
         m_A += ybar;
-        if (kbar < 0.0)
-        {
-            std::cerr << "YBAR: " << ybar << ", KBAR: " << kbar << std::endl;
-            abort();
-        }
         m_B += kbar - ybar;
 
-
         float var = get_var();
-        // std::cout << var << std::endl;
         if (var > Occupancy::var_thresh)
             state = State::UNKNOWN;
         else {
             float p = get_prob();
-            // if (p != 0.75) std::cout << "ERR: " <<  p << std::endl;
             state = p > Occupancy::occupied_thresh ? State::OCCUPIED : (p < Occupancy::free_thresh ? State::FREE
                                                                                                    : State::UNKNOWN);
         }
@@ -84,4 +60,4 @@ namespace la3dm {
     std::ostream &operator<<(std::ostream &os, const Occupancy &oc) {
         return os << '(' << oc.m_A << ' ' << oc.m_B << ' ' << oc.get_prob() << ')';
     }
-}
+}