DefaultOrderingFunc in EliminationTraits

gtsam/discrete/DiscreteFactorGraph.h

@@ -62,9 +62,17 @@ template<> struct EliminationTraits<DiscreteFactorGraph>
   typedef DiscreteBayesTree BayesTreeType;             ///< Type of Bayes tree
   typedef DiscreteJunctionTree JunctionTreeType;       ///< Type of Junction tree
   /// The default dense elimination function
-  static std::pair<boost::shared_ptr<ConditionalType>, boost::shared_ptr<FactorType> >
+  static std::pair<boost::shared_ptr<ConditionalType>,
+                   boost::shared_ptr<FactorType> >
   DefaultEliminate(const FactorGraphType& factors, const Ordering& keys) {
-    return EliminateDiscrete(factors, keys); }
+    return EliminateDiscrete(factors, keys);
+  }
+  /// The default ordering generation function
+  static Ordering DefaultOrderingFunc(
+      const FactorGraphType& graph,
+      boost::optional<const VariableIndex&> variableIndex) {
+    return Ordering::Colamd(*variableIndex);
+  }
 };
 
 /* ************************************************************************* */

gtsam/hybrid/HybridGaussianFactorGraph.cpp

@@ -58,6 +58,21 @@ namespace gtsam {
 /// Specialize EliminateableFactorGraph for HybridGaussianFactorGraph:
 template class EliminateableFactorGraph<HybridGaussianFactorGraph>;
 
+/* ************************************************************************ */
+const Ordering HybridOrdering(const HybridGaussianFactorGraph &graph) {
+  KeySet discrete_keys = graph.discreteKeys();
+  for (auto &factor : graph) {
+    for (const DiscreteKey &k : factor->discreteKeys()) {
+      discrete_keys.insert(k.first);
+    }
+  }
+
+  const VariableIndex index(graph);
+  Ordering ordering = Ordering::ColamdConstrainedLast(
+      index, KeyVector(discrete_keys.begin(), discrete_keys.end()), true);
+  return ordering;
+}
+
 /* ************************************************************************ */
 static GaussianFactorGraphTree addGaussian(
     const GaussianFactorGraphTree &gfgTree,
@@ -448,21 +463,6 @@ void HybridGaussianFactorGraph::add(DecisionTreeFactor::shared_ptr factor) {
   FactorGraph::add(boost::make_shared<HybridDiscreteFactor>(factor));
 }
 
-/* ************************************************************************ */
-const Ordering HybridGaussianFactorGraph::getHybridOrdering() const {
-  KeySet discrete_keys = discreteKeys();
-  for (auto &factor : factors_) {
-    for (const DiscreteKey &k : factor->discreteKeys()) {
-      discrete_keys.insert(k.first);
-    }
-  }
-
-  const VariableIndex index(factors_);
-  Ordering ordering = Ordering::ColamdConstrainedLast(
-      index, KeyVector(discrete_keys.begin(), discrete_keys.end()), true);
-  return ordering;
-}
-
 /* ************************************************************************ */
 AlgebraicDecisionTree<Key> HybridGaussianFactorGraph::error(
     const VectorValues &continuousValues) const {

gtsam/hybrid/HybridGaussianFactorGraph.h

@@ -53,6 +53,15 @@ GTSAM_EXPORT
 std::pair<boost::shared_ptr<HybridConditional>, HybridFactor::shared_ptr>
 EliminateHybrid(const HybridGaussianFactorGraph& factors, const Ordering& keys);
 
+/**
+ * @brief Return a Colamd constrained ordering where the discrete keys are
+ * eliminated after the continuous keys.
+ *
+ * @return const Ordering
+ */
+GTSAM_EXPORT const Ordering
+HybridOrdering(const HybridGaussianFactorGraph& graph);
+
 /* ************************************************************************* */
 template <>
 struct EliminationTraits<HybridGaussianFactorGraph> {
@@ -74,6 +83,12 @@ struct EliminationTraits<HybridGaussianFactorGraph> {
   DefaultEliminate(const FactorGraphType& factors, const Ordering& keys) {
     return EliminateHybrid(factors, keys);
   }
+  /// The default ordering generation function
+  static Ordering DefaultOrderingFunc(
+      const FactorGraphType& graph,
+      boost::optional<const VariableIndex&> variableIndex) {
+    return HybridOrdering(graph);
+  }
 };
 
 /**
@@ -228,14 +243,6 @@ class GTSAM_EXPORT HybridGaussianFactorGraph
    */
   double probPrime(const HybridValues& values) const;
 
-  /**
-   * @brief Return a Colamd constrained ordering where the discrete keys are
-   * eliminated after the continuous keys.
-   *
-   * @return const Ordering
-   */
-  const Ordering getHybridOrdering() const;
-
   /**
    * @brief Create a decision tree of factor graphs out of this hybrid factor
    * graph.

gtsam/hybrid/tests/testHybridBayesNet.cpp

@@ -185,9 +185,8 @@ TEST(HybridBayesNet, OptimizeAssignment) {
 TEST(HybridBayesNet, Optimize) {
   Switching s(4, 1.0, 0.1, {0, 1, 2, 3}, "1/1 1/1");
 
-  Ordering hybridOrdering = s.linearizedFactorGraph.getHybridOrdering();
   HybridBayesNet::shared_ptr hybridBayesNet =
-      s.linearizedFactorGraph.eliminateSequential(hybridOrdering);
+      s.linearizedFactorGraph.eliminateSequential();
 
   HybridValues delta = hybridBayesNet->optimize();
 
@@ -212,9 +211,8 @@ TEST(HybridBayesNet, Optimize) {
 TEST(HybridBayesNet, Error) {
   Switching s(3);
 
-  Ordering hybridOrdering = s.linearizedFactorGraph.getHybridOrdering();
   HybridBayesNet::shared_ptr hybridBayesNet =
-      s.linearizedFactorGraph.eliminateSequential(hybridOrdering);
+      s.linearizedFactorGraph.eliminateSequential();
 
   HybridValues delta = hybridBayesNet->optimize();
   auto error_tree = hybridBayesNet->error(delta.continuous());
@@ -266,9 +264,8 @@ TEST(HybridBayesNet, Error) {
 TEST(HybridBayesNet, Prune) {
   Switching s(4);
 
-  Ordering hybridOrdering = s.linearizedFactorGraph.getHybridOrdering();
   HybridBayesNet::shared_ptr hybridBayesNet =
-      s.linearizedFactorGraph.eliminateSequential(hybridOrdering);
+      s.linearizedFactorGraph.eliminateSequential();
 
   HybridValues delta = hybridBayesNet->optimize();
 
@@ -284,9 +281,8 @@ TEST(HybridBayesNet, Prune) {
 TEST(HybridBayesNet, UpdateDiscreteConditionals) {
   Switching s(4);
 
-  Ordering hybridOrdering = s.linearizedFactorGraph.getHybridOrdering();
   HybridBayesNet::shared_ptr hybridBayesNet =
-      s.linearizedFactorGraph.eliminateSequential(hybridOrdering);
+      s.linearizedFactorGraph.eliminateSequential();
 
   size_t maxNrLeaves = 3;
   auto discreteConditionals = hybridBayesNet->discreteConditionals();
@@ -353,8 +349,7 @@ TEST(HybridBayesNet, Sampling) {
   // Create the factor graph from the nonlinear factor graph.
   HybridGaussianFactorGraph::shared_ptr fg = nfg.linearize(initial);
   // Eliminate into BN
-  Ordering ordering = fg->getHybridOrdering();
-  HybridBayesNet::shared_ptr bn = fg->eliminateSequential(ordering);
+  HybridBayesNet::shared_ptr bn = fg->eliminateSequential();
 
   // Set up sampling
   std::mt19937_64 gen(11);

gtsam/hybrid/tests/testHybridBayesTree.cpp

@@ -37,9 +37,8 @@ using symbol_shorthand::X;
 TEST(HybridBayesTree, OptimizeMultifrontal) {
   Switching s(4);
 
-  Ordering hybridOrdering = s.linearizedFactorGraph.getHybridOrdering();
   HybridBayesTree::shared_ptr hybridBayesTree =
-      s.linearizedFactorGraph.eliminateMultifrontal(hybridOrdering);
+      s.linearizedFactorGraph.eliminateMultifrontal();
   HybridValues delta = hybridBayesTree->optimize();
 
   VectorValues expectedValues;
@@ -203,16 +202,8 @@ TEST(HybridBayesTree, Choose) {
 
   GaussianBayesTree gbt = isam.choose(assignment);
 
-  Ordering ordering;
-  ordering += X(0);
-  ordering += X(1);
-  ordering += X(2);
-  ordering += X(3);
-  ordering += M(0);
-  ordering += M(1);
-  ordering += M(2);
-
-  // TODO(Varun) get segfault if ordering not provided
+  // Specify ordering so it matches that of HybridGaussianISAM.
+  Ordering ordering(KeyVector{X(0), X(1), X(2), X(3), M(0), M(1), M(2)});
   auto bayesTree = s.linearizedFactorGraph.eliminateMultifrontal(ordering);
 
   auto expected_gbt = bayesTree->choose(assignment);

gtsam/hybrid/tests/testHybridEstimation.cpp

@@ -90,7 +90,7 @@ TEST(HybridEstimation, Full) {
   }
 
   HybridBayesNet::shared_ptr bayesNet =
-      graph.eliminateSequential(hybridOrdering);
+      graph.eliminateSequential();
 
   EXPECT_LONGS_EQUAL(2 * K - 1, bayesNet->size());
 
@@ -481,8 +481,7 @@ TEST(HybridEstimation, CorrectnessViaSampling) {
   const auto fg = createHybridGaussianFactorGraph();
 
   // 2. Eliminate into BN
-  const Ordering ordering = fg->getHybridOrdering();
-  const HybridBayesNet::shared_ptr bn = fg->eliminateSequential(ordering);
+  const HybridBayesNet::shared_ptr bn = fg->eliminateSequential();
 
   // Set up sampling
   std::mt19937_64 rng(11);

gtsam/hybrid/tests/testHybridGaussianFactorGraph.cpp

@@ -130,8 +130,7 @@ TEST(HybridGaussianFactorGraph, eliminateFullSequentialEqualChance) {
 
   hfg.add(GaussianMixtureFactor({X(1)}, {m1}, dt));
 
-  auto result =
-      hfg.eliminateSequential(Ordering::ColamdConstrainedLast(hfg, {M(1)}));
+  auto result = hfg.eliminateSequential();
 
   auto dc = result->at(2)->asDiscrete();
   DiscreteValues dv;
@@ -161,8 +160,7 @@ TEST(HybridGaussianFactorGraph, eliminateFullSequentialSimple) {
   // Joint discrete probability table for c1, c2
   hfg.add(DecisionTreeFactor({{M(1), 2}, {M(2), 2}}, "1 2 3 4"));
 
-  HybridBayesNet::shared_ptr result = hfg.eliminateSequential(
-      Ordering::ColamdConstrainedLast(hfg, {M(1), M(2)}));
+  HybridBayesNet::shared_ptr result = hfg.eliminateSequential();
 
   // There are 4 variables (2 continuous + 2 discrete) in the bayes net.
   EXPECT_LONGS_EQUAL(4, result->size());
@@ -187,8 +185,7 @@ TEST(HybridGaussianFactorGraph, eliminateFullMultifrontalSimple) {
   // variable throws segfault
   //  hfg.add(DecisionTreeFactor({{M(1), 2}, {M(2), 2}}, "1 2 3 4"));
 
-  HybridBayesTree::shared_ptr result =
-      hfg.eliminateMultifrontal(hfg.getHybridOrdering());
+  HybridBayesTree::shared_ptr result = hfg.eliminateMultifrontal();
 
   // The bayes tree should have 3 cliques
   EXPECT_LONGS_EQUAL(3, result->size());
@@ -218,7 +215,7 @@ TEST(HybridGaussianFactorGraph, eliminateFullMultifrontalCLG) {
   hfg.add(HybridDiscreteFactor(DecisionTreeFactor(m, {2, 8})));
 
   // Get a constrained ordering keeping c1 last
-  auto ordering_full = hfg.getHybridOrdering();
+  auto ordering_full = HybridOrdering(hfg);
 
   // Returns a Hybrid Bayes Tree with distribution P(x0|x1)P(x1|c1)P(c1)
   HybridBayesTree::shared_ptr hbt = hfg.eliminateMultifrontal(ordering_full);
@@ -518,8 +515,7 @@ TEST(HybridGaussianFactorGraph, optimize) {
 
   hfg.add(GaussianMixtureFactor({X(1)}, {c1}, dt));
 
-  auto result =
-      hfg.eliminateSequential(Ordering::ColamdConstrainedLast(hfg, {C(1)}));
+  auto result = hfg.eliminateSequential();
 
   HybridValues hv = result->optimize();
 
@@ -572,9 +568,7 @@ TEST(HybridGaussianFactorGraph, ErrorAndProbPrime) {
 
   HybridGaussianFactorGraph graph = s.linearizedFactorGraph;
 
-  Ordering hybridOrdering = graph.getHybridOrdering();
-  HybridBayesNet::shared_ptr hybridBayesNet =
-      graph.eliminateSequential(hybridOrdering);
+  HybridBayesNet::shared_ptr hybridBayesNet = graph.eliminateSequential();
 
   const HybridValues delta = hybridBayesNet->optimize();
   const double error = graph.error(delta);
@@ -593,9 +587,7 @@ TEST(HybridGaussianFactorGraph, ErrorAndProbPrimeTree) {
 
   HybridGaussianFactorGraph graph = s.linearizedFactorGraph;
 
-  Ordering hybridOrdering = graph.getHybridOrdering();
-  HybridBayesNet::shared_ptr hybridBayesNet =
-      graph.eliminateSequential(hybridOrdering);
+  HybridBayesNet::shared_ptr hybridBayesNet = graph.eliminateSequential();
 
   HybridValues delta = hybridBayesNet->optimize();
   auto error_tree = graph.error(delta.continuous());
@@ -684,10 +676,7 @@ TEST(HybridGaussianFactorGraph, EliminateTiny1) {
   expectedBayesNet.emplace_back(new DiscreteConditional(mode, "74/26"));
 
   // Test elimination
-  Ordering ordering;
-  ordering.push_back(X(0));
-  ordering.push_back(M(0));
-  const auto posterior = fg.eliminateSequential(ordering);
+  const auto posterior = fg.eliminateSequential();
   EXPECT(assert_equal(expectedBayesNet, *posterior, 0.01));
 }
 
@@ -719,10 +708,7 @@ TEST(HybridGaussianFactorGraph, EliminateTiny2) {
   expectedBayesNet.emplace_back(new DiscreteConditional(mode, "23/77"));
 
   // Test elimination
-  Ordering ordering;
-  ordering.push_back(X(0));
-  ordering.push_back(M(0));
-  const auto posterior = fg.eliminateSequential(ordering);
+  const auto posterior = fg.eliminateSequential();
   EXPECT(assert_equal(expectedBayesNet, *posterior, 0.01));
 }
 
@@ -741,11 +727,7 @@ TEST(HybridGaussianFactorGraph, EliminateTiny22) {
   EXPECT_LONGS_EQUAL(5, fg.size());
 
   // Test elimination
-  Ordering ordering;
-  ordering.push_back(X(0));
-  ordering.push_back(M(0));
-  ordering.push_back(M(1));
-  const auto posterior = fg.eliminateSequential(ordering);
+  const auto posterior = fg.eliminateSequential();
 
   // Compute the log-ratio between the Bayes net and the factor graph.
   auto compute_ratio = [&](HybridValues *sample) -> double {

gtsam/hybrid/tests/testSerializationHybrid.cpp

@@ -150,8 +150,7 @@ TEST(HybridSerialization, GaussianMixture) {
 // Test HybridBayesNet serialization.
 TEST(HybridSerialization, HybridBayesNet) {
   Switching s(2);
-  Ordering ordering = s.linearizedFactorGraph.getHybridOrdering();
-  HybridBayesNet hbn = *(s.linearizedFactorGraph.eliminateSequential(ordering));
+  HybridBayesNet hbn = *(s.linearizedFactorGraph.eliminateSequential());
 
   EXPECT(equalsObj<HybridBayesNet>(hbn));
   EXPECT(equalsXML<HybridBayesNet>(hbn));
@@ -162,9 +161,7 @@ TEST(HybridSerialization, HybridBayesNet) {
 // Test HybridBayesTree serialization.
 TEST(HybridSerialization, HybridBayesTree) {
   Switching s(2);
-  Ordering ordering = s.linearizedFactorGraph.getHybridOrdering();
-  HybridBayesTree hbt =
-      *(s.linearizedFactorGraph.eliminateMultifrontal(ordering));
+  HybridBayesTree hbt = *(s.linearizedFactorGraph.eliminateMultifrontal());
 
   EXPECT(equalsObj<HybridBayesTree>(hbt));
   EXPECT(equalsXML<HybridBayesTree>(hbt));

gtsam/inference/EliminateableFactorGraph-inst.h

@@ -44,9 +44,16 @@ namespace gtsam {
       if (orderingType == Ordering::METIS) {
         Ordering computedOrdering = Ordering::Metis(asDerived());
         return eliminateSequential(computedOrdering, function, variableIndex);
-      } else {
+      } else if (orderingType == Ordering::COLAMD) {
         Ordering computedOrdering = Ordering::Colamd(*variableIndex);
         return eliminateSequential(computedOrdering, function, variableIndex);
+      } else if (orderingType == Ordering::NATURAL) {
+        Ordering computedOrdering = Ordering::Natural(asDerived());
+        return eliminateSequential(computedOrdering, function, variableIndex);
+      } else {
+        Ordering computedOrdering = EliminationTraitsType::DefaultOrderingFunc(
+            asDerived(), variableIndex);
+        return eliminateSequential(computedOrdering, function, variableIndex);
       }
     }
   }
@@ -100,9 +107,16 @@ namespace gtsam {
       if (orderingType == Ordering::METIS) {
         Ordering computedOrdering = Ordering::Metis(asDerived());
         return eliminateMultifrontal(computedOrdering, function, variableIndex);
-      } else {
+      } else if (orderingType == Ordering::COLAMD) {
         Ordering computedOrdering = Ordering::Colamd(*variableIndex);
         return eliminateMultifrontal(computedOrdering, function, variableIndex);
+      } else if (orderingType == Ordering::NATURAL) {
+        Ordering computedOrdering = Ordering::Natural(asDerived());
+        return eliminateMultifrontal(computedOrdering, function, variableIndex);
+      } else {
+        Ordering computedOrdering = EliminationTraitsType::DefaultOrderingFunc(
+            asDerived(), variableIndex);
+        return eliminateMultifrontal(computedOrdering, function, variableIndex);
       }
     }
   }

gtsam/linear/GaussianFactorGraph.h

@@ -54,6 +54,12 @@ namespace gtsam {
     static std::pair<boost::shared_ptr<ConditionalType>, boost::shared_ptr<FactorType> >
       DefaultEliminate(const FactorGraphType& factors, const Ordering& keys) {
         return EliminatePreferCholesky(factors, keys); }
+    /// The default ordering generation function
+    static Ordering DefaultOrderingFunc(
+        const FactorGraphType& graph,
+        boost::optional<const VariableIndex&> variableIndex) {
+      return Ordering::Colamd(*variableIndex);
+    }
   };
 
   /* ************************************************************************* */