update hybrid elimination and corresponding tests

gtsam/hybrid/HybridGaussianFactorGraph.cpp

@@ -172,8 +172,13 @@ discreteElimination(const HybridGaussianFactorGraph &factors,
     }
   }
 
+  // std::cout << "Eliminate For MPE" << std::endl;
   auto result = EliminateForMPE(dfg, frontalKeys);
-
+  // std::cout << "discrete elimination done!" << std::endl;
+  // dfg.print();
+  // std::cout << "\n\n\n" << std::endl;
+  // result.first->print();
+  // result.second->print();
   return {boost::make_shared<HybridConditional>(result.first),
           boost::make_shared<HybridDiscreteFactor>(result.second)};
 }
@@ -262,7 +267,9 @@ hybridElimination(const HybridGaussianFactorGraph &factors,
       if (!factor) {
         return 0.0;  // If nullptr, return 0.0 probability
       } else {
-        return 1.0;
+        double error =
+            0.5 * std::abs(factor->augmentedInformation().determinant());
+        return std::exp(-error);
       }
     };
     DecisionTree<Key, double> fdt(separatorFactors, factorProb);
@@ -550,5 +557,4 @@ HybridGaussianFactorGraph::separateContinuousDiscreteOrdering(
   return std::make_pair(continuous_ordering, discrete_ordering);
 }
 
-
 }  // namespace gtsam

gtsam/hybrid/HybridSmoother.cpp

@@ -32,7 +32,7 @@ void HybridSmoother::update(HybridGaussianFactorGraph graph,
       addConditionals(graph, hybridBayesNet_, ordering);
 
   // Eliminate.
-  auto bayesNetFragment = graph.eliminateSequential();
+  auto bayesNetFragment = graph.eliminateSequential(ordering);
 
   /// Prune
   if (maxNrLeaves) {

gtsam/hybrid/tests/testHybridEstimation.cpp

@@ -15,6 +15,7 @@
  * @author  Varun Agrawal
  */
 
+#include <gtsam/discrete/DiscreteBayesNet.h>
 #include <gtsam/geometry/Pose2.h>
 #include <gtsam/hybrid/HybridBayesNet.h>
 #include <gtsam/hybrid/HybridNonlinearFactorGraph.h>
@@ -280,8 +281,10 @@ TEST(HybridEstimation, Probability) {
 
     VectorValues values = bayes_net->optimize();
 
-    expected_errors.push_back(linear_graph->error(values));
-    expected_prob_primes.push_back(linear_graph->probPrime(values));
+    double error = linear_graph->error(values);
+    expected_errors.push_back(error);
+    double prob_prime = linear_graph->probPrime(values);
+    expected_prob_primes.push_back(prob_prime);
   }
 
   // Switching example of robot moving in 1D with given measurements and equal
@@ -291,51 +294,21 @@ TEST(HybridEstimation, Probability) {
   auto graph = switching.linearizedFactorGraph;
   Ordering ordering = getOrdering(graph, HybridGaussianFactorGraph());
 
-  AlgebraicDecisionTree<Key> expected_probPrimeTree = probPrimeTree(graph);
-
-  // Eliminate continuous
-  Ordering continuous_ordering(graph.continuousKeys());
-  HybridBayesNet::shared_ptr bayesNet;
-  HybridGaussianFactorGraph::shared_ptr discreteGraph;
-  std::tie(bayesNet, discreteGraph) =
-      graph.eliminatePartialSequential(continuous_ordering);
-
-  // Get the last continuous conditional which will have all the discrete keys
-  auto last_conditional = bayesNet->at(bayesNet->size() - 1);
-  DiscreteKeys discrete_keys = last_conditional->discreteKeys();
-
-  const std::vector<DiscreteValues> assignments =
-      DiscreteValues::CartesianProduct(discrete_keys);
-
-  // Reverse discrete keys order for correct tree construction
-  std::reverse(discrete_keys.begin(), discrete_keys.end());
-
-  // Create a decision tree of all the different VectorValues
-  DecisionTree<Key, VectorValues::shared_ptr> delta_tree =
-      graph.continuousDelta(discrete_keys, bayesNet, assignments);
-
-  AlgebraicDecisionTree<Key> probPrimeTree =
-      graph.continuousProbPrimes(discrete_keys, bayesNet);
-
-  EXPECT(assert_equal(expected_probPrimeTree, probPrimeTree));
+  HybridBayesNet::shared_ptr bayesNet = graph.eliminateSequential(ordering);
+  auto discreteConditional = bayesNet->atDiscrete(bayesNet->size() - 3);
 
   // Test if the probPrimeTree matches the probability of
   // the individual factor graphs
   for (size_t i = 0; i < pow(2, K - 1); i++) {
-    Assignment<Key> discrete_assignment;
+    DiscreteValues discrete_assignment;
     for (size_t v = 0; v < discrete_seq_map[i].size(); v++) {
       discrete_assignment[M(v)] = discrete_seq_map[i][v];
     }
-    EXPECT_DOUBLES_EQUAL(expected_prob_primes.at(i),
-                         probPrimeTree(discrete_assignment), 1e-8);
+    double discrete_transition_prob = 0.25;
+    EXPECT_DOUBLES_EQUAL(expected_prob_primes.at(i) * discrete_transition_prob,
+                         (*discreteConditional)(discrete_assignment), 1e-8);
   }
 
-  discreteGraph->add(DecisionTreeFactor(discrete_keys, probPrimeTree));
-
-  Ordering discrete(graph.discreteKeys());
-  auto discreteBayesNet = discreteGraph->eliminateSequential();
-  bayesNet->add(*discreteBayesNet);
-
   HybridValues hybrid_values = bayesNet->optimize();
 
   // This is the correct sequence as designed

gtsam/hybrid/tests/testHybridGaussianFactorGraph.cpp

@@ -277,7 +277,7 @@ TEST(HybridGaussianFactorGraph, eliminateFullMultifrontalTwoClique) {
   std::tie(hbt, remaining) = hfg.eliminatePartialMultifrontal(ordering_full);
 
   // 9 cliques in the bayes tree and 0 remaining variables to eliminate.
-  EXPECT_LONGS_EQUAL(7, hbt->size());
+  EXPECT_LONGS_EQUAL(9, hbt->size());
   EXPECT_LONGS_EQUAL(0, remaining->size());
 
   /*

gtsam/hybrid/tests/testHybridGaussianISAM.cpp

@@ -178,7 +178,7 @@ TEST(HybridGaussianElimination, IncrementalInference) {
 
   // Test the probability values with regression tests.
   DiscreteValues assignment;
-  EXPECT(assert_equal(0.166667, m00_prob, 1e-5));
+  EXPECT(assert_equal(0.0619233, m00_prob, 1e-5));
   assignment[M(0)] = 0;
   assignment[M(1)] = 0;
   EXPECT(assert_equal(0.0619233, (*discreteConditional)(assignment), 1e-5));

gtsam/hybrid/tests/testHybridNonlinearFactorGraph.cpp

@@ -372,8 +372,7 @@ TEST(HybridGaussianElimination, EliminateHybrid_2_Variable) {
       dynamic_pointer_cast<DecisionTreeFactor>(hybridDiscreteFactor->inner());
   CHECK(discreteFactor);
   EXPECT_LONGS_EQUAL(1, discreteFactor->discreteKeys().size());
-  // All leaves should be probability 1 since this is not P*(X|M,Z)
-  EXPECT(discreteFactor->root_->isLeaf());
+  EXPECT(discreteFactor->root_->isLeaf() == false);
 
   // TODO(Varun) Test emplace_discrete
 }
@@ -441,14 +440,6 @@ TEST(HybridFactorGraph, Full_Elimination) {
       discrete_fg.push_back(df->inner());
     }
 
-    // Get the probabilit P*(X | M, Z)
-    DiscreteKeys discrete_keys =
-        remainingFactorGraph_partial->at(2)->discreteKeys();
-    AlgebraicDecisionTree<Key> probPrimeTree =
-        linearizedFactorGraph.continuousProbPrimes(discrete_keys,
-                                                   hybridBayesNet_partial);
-    discrete_fg.add(DecisionTreeFactor(discrete_keys, probPrimeTree));
-
     ordering.clear();
     for (size_t k = 0; k < self.K - 1; k++) ordering += M(k);
     discreteBayesNet =

gtsam/hybrid/tests/testHybridNonlinearISAM.cpp

@@ -197,7 +197,7 @@ TEST(HybridNonlinearISAM, IncrementalInference) {
 
   // Test the probability values with regression tests.
   DiscreteValues assignment;
-  EXPECT(assert_equal(0.166667, m00_prob, 1e-5));
+  EXPECT(assert_equal(0.0619233, m00_prob, 1e-5));
   assignment[M(0)] = 0;
   assignment[M(1)] = 0;
   EXPECT(assert_equal(0.0619233, (*discreteConditional)(assignment), 1e-5));