Merge pull request #1669 from borglab/discrete-error

gtsam/discrete/DecisionTreeFactor.cpp

@@ -62,6 +62,22 @@ namespace gtsam {
     return error(values.discrete());
   }
 
+  /* ************************************************************************ */
+  AlgebraicDecisionTree<Key> DecisionTreeFactor::errorTree() const {
+    // Get all possible assignments
+    DiscreteKeys dkeys = discreteKeys();
+    // Reverse to make cartesian product output a more natural ordering.
+    DiscreteKeys rdkeys(dkeys.rbegin(), dkeys.rend());
+    const auto assignments = DiscreteValues::CartesianProduct(rdkeys);
+
+    // Construct vector with error values
+    std::vector<double> errors;
+    for (const auto& assignment : assignments) {
+      errors.push_back(error(assignment));
+    }
+    return AlgebraicDecisionTree<Key>(dkeys, errors);
+  }
+
   /* ************************************************************************ */
   double DecisionTreeFactor::safe_div(const double& a, const double& b) {
     // The use for safe_div is when we divide the product factor by the sum

gtsam/discrete/DecisionTreeFactor.h

@@ -292,6 +292,9 @@ namespace gtsam {
    */
   double error(const HybridValues& values) const override;
 
+  /// Compute error for each assignment and return as a tree
+  AlgebraicDecisionTree<Key> errorTree() const override;
+
   /// @}
 
    private:

gtsam/discrete/DiscreteFactor.h

@@ -18,9 +18,10 @@
 
 #pragma once
 
+#include <gtsam/base/Testable.h>
+#include <gtsam/discrete/AlgebraicDecisionTree.h>
 #include <gtsam/discrete/DiscreteValues.h>
 #include <gtsam/inference/Factor.h>
-#include <gtsam/base/Testable.h>
 
 #include <string>
 namespace gtsam {
@@ -35,7 +36,7 @@ class HybridValues;
  *
  * @ingroup discrete
  */
-class GTSAM_EXPORT DiscreteFactor: public Factor {
+class GTSAM_EXPORT DiscreteFactor : public Factor {
  public:
   // typedefs needed to play nice with gtsam
   typedef DiscreteFactor This;  ///< This class
@@ -103,15 +104,19 @@ class GTSAM_EXPORT DiscreteFactor: public Factor {
    */
   double error(const HybridValues& c) const override;
 
-  /// Multiply in a DecisionTreeFactor and return the result as DecisionTreeFactor
+  /// Compute error for each assignment and return as a tree
+  virtual AlgebraicDecisionTree<Key> errorTree() const = 0;
+
+  /// Multiply in a DecisionTreeFactor and return the result as
+  /// DecisionTreeFactor
   virtual DecisionTreeFactor operator*(const DecisionTreeFactor&) const = 0;
 
   virtual DecisionTreeFactor toDecisionTreeFactor() const = 0;
 
   /// @}
   /// @name Wrapper support
   /// @{
-  
+
   /// Translation table from values to strings.
   using Names = DiscreteValues::Names;
 
@@ -175,4 +180,4 @@ template<> struct traits<DiscreteFactor> : public Testable<DiscreteFactor> {};
 std::vector<double> expNormalize(const std::vector<double> &logProbs);
 
 
-}// namespace gtsam
+}  // namespace gtsam

gtsam/discrete/TableFactor.cpp

@@ -168,6 +168,11 @@ double TableFactor::error(const HybridValues& values) const {
   return error(values.discrete());
 }
 
+/* ************************************************************************ */
+AlgebraicDecisionTree<Key> TableFactor::errorTree() const {
+  return toDecisionTreeFactor().errorTree();
+}
+
 /* ************************************************************************ */
 DecisionTreeFactor TableFactor::operator*(const DecisionTreeFactor& f) const {
   return toDecisionTreeFactor() * f;

gtsam/discrete/TableFactor.h

@@ -358,6 +358,9 @@ class GTSAM_EXPORT TableFactor : public DiscreteFactor {
    */
   double error(const HybridValues& values) const override;
 
+  /// Compute error for each assignment and return as a tree
+  AlgebraicDecisionTree<Key> errorTree() const override;
+
   /// @}
 };
 

gtsam/discrete/tests/testDecisionTreeFactor.cpp

@@ -67,6 +67,24 @@ TEST( DecisionTreeFactor, constructors)
   EXPECT_DOUBLES_EQUAL(0.8, f4(x121), 1e-9);
 }
 
+/* ************************************************************************* */
+TEST(DecisionTreeFactor, Error) {
+  // Declare a bunch of keys
+  DiscreteKey X(0,2), Y(1,3), Z(2,2);
+
+  // Create factors
+  DecisionTreeFactor f(X & Y & Z, "2 5 3 6 4 7 25 55 35 65 45 75");
+
+  auto errors = f.errorTree();
+  // regression
+  AlgebraicDecisionTree<Key> expected(
+      {X, Y, Z},
+      vector<double>{-0.69314718, -1.6094379, -1.0986123, -1.7917595,
+                     -1.3862944, -1.9459101, -3.2188758, -4.0073332, -3.5553481,
+                     -4.1743873, -3.8066625, -4.3174881});
+  EXPECT(assert_equal(expected, errors, 1e-6));
+}
+
 /* ************************************************************************* */
 TEST(DecisionTreeFactor, multiplication) {
   DiscreteKey v0(0, 2), v1(1, 2), v2(2, 2);

gtsam/hybrid/GaussianMixture.cpp

@@ -313,14 +313,14 @@ AlgebraicDecisionTree<Key> GaussianMixture::logProbability(
 }
 
 /* *******************************************************************************/
-AlgebraicDecisionTree<Key> GaussianMixture::error(
+AlgebraicDecisionTree<Key> GaussianMixture::errorTree(
     const VectorValues &continuousValues) const {
   auto errorFunc = [&](const GaussianConditional::shared_ptr &conditional) {
     return conditional->error(continuousValues) +  //
            logConstant_ - conditional->logNormalizationConstant();
   };
-  DecisionTree<Key, double> errorTree(conditionals_, errorFunc);
-  return errorTree;
+  DecisionTree<Key, double> error_tree(conditionals_, errorFunc);
+  return error_tree;
 }
 
 /* *******************************************************************************/

gtsam/hybrid/GaussianMixture.h

@@ -214,7 +214,7 @@ class GTSAM_EXPORT GaussianMixture
    * @return AlgebraicDecisionTree<Key> A decision tree on the discrete keys
    * only, with the leaf values as the error for each assignment.
    */
-  AlgebraicDecisionTree<Key> error(const VectorValues &continuousValues) const;
+  AlgebraicDecisionTree<Key> errorTree(const VectorValues &continuousValues) const;
 
   /**
    * @brief Compute the logProbability of this Gaussian Mixture.

gtsam/hybrid/GaussianMixtureFactor.cpp

@@ -102,14 +102,14 @@ GaussianFactorGraphTree GaussianMixtureFactor::asGaussianFactorGraphTree()
 }
 
 /* *******************************************************************************/
-AlgebraicDecisionTree<Key> GaussianMixtureFactor::error(
+AlgebraicDecisionTree<Key> GaussianMixtureFactor::errorTree(
     const VectorValues &continuousValues) const {
   // functor to convert from sharedFactor to double error value.
   auto errorFunc = [&continuousValues](const sharedFactor &gf) {
     return gf->error(continuousValues);
   };
-  DecisionTree<Key, double> errorTree(factors_, errorFunc);
-  return errorTree;
+  DecisionTree<Key, double> error_tree(factors_, errorFunc);
+  return error_tree;
 }
 
 /* *******************************************************************************/

gtsam/hybrid/GaussianMixtureFactor.h

@@ -135,7 +135,7 @@ class GTSAM_EXPORT GaussianMixtureFactor : public HybridFactor {
    * @return AlgebraicDecisionTree<Key> A decision tree with the same keys
    * as the factors involved, and leaf values as the error.
    */
-  AlgebraicDecisionTree<Key> error(const VectorValues &continuousValues) const;
+  AlgebraicDecisionTree<Key> errorTree(const VectorValues &continuousValues) const;
 
   /**
    * @brief Compute the log-likelihood, including the log-normalizing constant.

gtsam/hybrid/HybridGaussianFactorGraph.cpp

@@ -420,7 +420,7 @@ EliminateHybrid(const HybridGaussianFactorGraph &factors,
 }
 
 /* ************************************************************************ */
-AlgebraicDecisionTree<Key> HybridGaussianFactorGraph::error(
+AlgebraicDecisionTree<Key> HybridGaussianFactorGraph::errorTree(
     const VectorValues &continuousValues) const {
   AlgebraicDecisionTree<Key> error_tree(0.0);
 
@@ -431,7 +431,7 @@ AlgebraicDecisionTree<Key> HybridGaussianFactorGraph::error(
 
     if (auto gaussianMixture = dynamic_pointer_cast<GaussianMixtureFactor>(f)) {
       // Compute factor error and add it.
-      error_tree = error_tree + gaussianMixture->error(continuousValues);
+      error_tree = error_tree + gaussianMixture->errorTree(continuousValues);
     } else if (auto gaussian = dynamic_pointer_cast<GaussianFactor>(f)) {
       // If continuous only, get the (double) error
       // and add it to the error_tree
@@ -460,7 +460,7 @@ double HybridGaussianFactorGraph::probPrime(const HybridValues &values) const {
 /* ************************************************************************ */
 AlgebraicDecisionTree<Key> HybridGaussianFactorGraph::probPrime(
     const VectorValues &continuousValues) const {
-  AlgebraicDecisionTree<Key> error_tree = this->error(continuousValues);
+  AlgebraicDecisionTree<Key> error_tree = this->errorTree(continuousValues);
   AlgebraicDecisionTree<Key> prob_tree = error_tree.apply([](double error) {
     // NOTE: The 0.5 term is handled by each factor
     return exp(-error);

gtsam/hybrid/HybridGaussianFactorGraph.h

@@ -161,7 +161,8 @@ class GTSAM_EXPORT HybridGaussianFactorGraph
    * @param continuousValues Continuous values at which to compute the error.
    * @return AlgebraicDecisionTree<Key>
    */
-  AlgebraicDecisionTree<Key> error(const VectorValues& continuousValues) const;
+  AlgebraicDecisionTree<Key> errorTree(
+      const VectorValues& continuousValues) const;
 
   /**
    * @brief Compute unnormalized probability \f$ P(X | M, Z) \f$

gtsam/hybrid/MixtureFactor.h

@@ -131,13 +131,13 @@ class MixtureFactor : public HybridFactor {
    * @return AlgebraicDecisionTree<Key> A decision tree with the same keys
    * as the factor, and leaf values as the error.
    */
-  AlgebraicDecisionTree<Key> error(const Values& continuousValues) const {
+  AlgebraicDecisionTree<Key> errorTree(const Values& continuousValues) const {
     // functor to convert from sharedFactor to double error value.
     auto errorFunc = [continuousValues](const sharedFactor& factor) {
       return factor->error(continuousValues);
     };
-    DecisionTree<Key, double> errorTree(factors_, errorFunc);
-    return errorTree;
+    DecisionTree<Key, double> result(factors_, errorFunc);
+    return result;
   }
 
   /**

gtsam/hybrid/tests/testGaussianMixture.cpp

@@ -97,7 +97,7 @@ TEST(GaussianMixture, LogProbability) {
 /// Check error.
 TEST(GaussianMixture, Error) {
   using namespace equal_constants;
-  auto actual = mixture.error(vv);
+  auto actual = mixture.errorTree(vv);
 
   // Check result.
   std::vector<DiscreteKey> discrete_keys = {mode};
@@ -134,7 +134,7 @@ TEST(GaussianMixture, Likelihood) {
   std::vector<double> leaves = {conditionals[0]->likelihood(vv)->error(vv),
                                 conditionals[1]->likelihood(vv)->error(vv)};
   AlgebraicDecisionTree<Key> expected(discrete_keys, leaves);
-  EXPECT(assert_equal(expected, likelihood->error(vv), 1e-6));
+  EXPECT(assert_equal(expected, likelihood->errorTree(vv), 1e-6));
 
   // Check that the ratio of probPrime to evaluate is the same for all modes.
   std::vector<double> ratio(2);

gtsam/hybrid/tests/testGaussianMixtureFactor.cpp

@@ -178,7 +178,7 @@ TEST(GaussianMixtureFactor, Error) {
   continuousValues.insert(X(2), Vector2(1, 1));
 
   // error should return a tree of errors, with nodes for each discrete value.
-  AlgebraicDecisionTree<Key> error_tree = mixtureFactor.error(continuousValues);
+  AlgebraicDecisionTree<Key> error_tree = mixtureFactor.errorTree(continuousValues);
 
   std::vector<DiscreteKey> discrete_keys = {m1};
   // Error values for regression test

gtsam/hybrid/tests/testHybridGaussianFactorGraph.cpp

@@ -580,7 +580,7 @@ TEST(HybridGaussianFactorGraph, ErrorAndProbPrimeTree) {
   HybridBayesNet::shared_ptr hybridBayesNet = graph.eliminateSequential();
 
   HybridValues delta = hybridBayesNet->optimize();
-  auto error_tree = graph.error(delta.continuous());
+  auto error_tree = graph.errorTree(delta.continuous());
 
   std::vector<DiscreteKey> discrete_keys = {{M(0), 2}, {M(1), 2}};
   std::vector<double> leaves = {0.9998558, 0.4902432, 0.5193694, 0.0097568};

gtsam/hybrid/tests/testMixtureFactor.cpp

@@ -97,7 +97,8 @@ TEST(MixtureFactor, Error) {
   continuousValues.insert<double>(X(1), 0);
   continuousValues.insert<double>(X(2), 1);
 
-  AlgebraicDecisionTree<Key> error_tree = mixtureFactor.error(continuousValues);
+  AlgebraicDecisionTree<Key> error_tree =
+      mixtureFactor.errorTree(continuousValues);
 
   DiscreteKey m1(1, 2);
   std::vector<DiscreteKey> discrete_keys = {m1};

gtsam_unstable/discrete/AllDiff.h

@@ -53,6 +53,11 @@ class GTSAM_UNSTABLE_EXPORT AllDiff : public Constraint {
   /// Multiply into a decisiontree
   DecisionTreeFactor operator*(const DecisionTreeFactor& f) const override;
 
+  /// Compute error for each assignment and return as a tree
+  AlgebraicDecisionTree<Key> errorTree() const override {
+    throw std::runtime_error("AllDiff::error not implemented");
+  }
+
   /*
    * Ensure Arc-consistency by checking every possible value of domain j.
    * @param j domain to be checked

gtsam_unstable/discrete/BinaryAllDiff.h

@@ -91,6 +91,11 @@ class BinaryAllDiff : public Constraint {
       const Domains&) const override {
     throw std::runtime_error("BinaryAllDiff::partiallyApply not implemented");
   }
+
+  /// Compute error for each assignment and return as a tree
+  AlgebraicDecisionTree<Key> errorTree() const override {
+    throw std::runtime_error("BinaryAllDiff::error not implemented");
+  }
 };
 
 }  // namespace gtsam

gtsam_unstable/discrete/Domain.h

@@ -69,6 +69,11 @@ class GTSAM_UNSTABLE_EXPORT Domain : public Constraint {
     }
   }
 
+  /// Compute error for each assignment and return as a tree
+  AlgebraicDecisionTree<Key> errorTree() const override {
+    throw std::runtime_error("Domain::error not implemented");
+  }
+
   // Return concise string representation, mostly to debug arc consistency.
   // Converts from base 0 to base1.
   std::string base1Str() const;

gtsam_unstable/discrete/SingleValue.h

@@ -49,6 +49,11 @@ class GTSAM_UNSTABLE_EXPORT SingleValue : public Constraint {
     }
   }
 
+  /// Compute error for each assignment and return as a tree
+  AlgebraicDecisionTree<Key> errorTree() const override {
+    throw std::runtime_error("SingleValue::error not implemented");
+  }
+
   /// Calculate value
   double operator()(const DiscreteValues& values) const override;