test in place for DiscreteMarginals

gtsam/discrete/DiscreteMarginals.h

@@ -0,0 +1,62 @@
+/* ----------------------------------------------------------------------------
+
+ * GTSAM Copyright 2010, Georgia Tech Research Corporation, 
+ * Atlanta, Georgia 30332-0415
+ * All Rights Reserved
+ * Authors: Frank Dellaert, et al. (see THANKS for the full author list)
+
+ * See LICENSE for the license information
+
+ * -------------------------------------------------------------------------- */
+
+/**
+ * @file DiscreteMarginals.h
+ * @brief A class for computing marginals in a DiscreteFactorGraph
+ * @author Abhijit Kundu
+ * @author Richard Roberts
+ * @author Frank Dellaert
+ * @date June 4, 2012
+ */
+
+#pragma once
+
+#include <gtsam/discrete/DiscreteFactorGraph.h>
+
+namespace gtsam {
+
+  /**
+   * A class for computing marginals of variables in a DiscreteFactorGraph
+   */
+  class DiscreteMarginals {
+
+  protected:
+
+    BayesTree<DiscreteConditional> bayesTree_;
+
+  public:
+
+    /** Construct a marginals class.
+     * @param graph The factor graph defining the full joint density on all variables.
+     */
+    DiscreteMarginals(const DiscreteFactorGraph& graph) {
+    }
+
+    /** print */
+    void print(const std::string& str = "DiscreteMarginals: ") const {
+    }
+
+    /** Compute the marginal of a single variable */
+    DiscreteFactor::shared_ptr operator()(Index variable) const {
+      DiscreteFactor::shared_ptr p;
+      return p;
+    }
+
+    /** Compute the marginal of a single variable */
+    Vector marginalProbabilities(Index variable) const {
+      Vector v;
+      return v;
+    }
+
+  };
+
+} /* namespace gtsam */

gtsam/discrete/tests/testDiscreteMarginals.cpp

@@ -0,0 +1,62 @@
+/* ----------------------------------------------------------------------------
+
+ * GTSAM Copyright 2010, Georgia Tech Research Corporation,
+ * Atlanta, Georgia 30332-0415
+ * All Rights Reserved
+ * Authors: Frank Dellaert, et al. (see THANKS for the full author list)
+
+ * See LICENSE for the license information
+
+ * -------------------------------------------------------------------------- */
+
+/*
+ * @ file testDiscreteMarginals.cpp
+ * @date Feb 14, 2011
+ * @author Abhijit Kundu
+ * @author Richard Roberts
+ * @author Frank Dellaert
+ */
+
+#include <gtsam/discrete/DiscreteMarginals.h>
+#include <CppUnitLite/TestHarness.h>
+
+using namespace std;
+using namespace gtsam;
+
+/* ************************************************************************* */
+
+TEST( DiscreteMarginals, UGM_small ) {
+  size_t nrStates = 2;
+  DiscreteKey Cathy(1, nrStates), Heather(2, nrStates), Mark(3, nrStates),
+      Allison(4, nrStates);
+  DiscreteFactorGraph graph;
+
+  // add node potentials
+  graph.add(Cathy, "1 3");
+  graph.add(Heather, "9 1");
+  graph.add(Mark, "1 3");
+  graph.add(Allison, "9 1");
+
+  // add edge potentials
+  graph.add(Cathy & Heather, "2 1 1 2");
+  graph.add(Heather & Mark, "2 1 1 2");
+  graph.add(Mark & Allison, "2 1 1 2");
+
+  DiscreteMarginals marginals(graph);
+
+  DiscreteFactor::shared_ptr actualC = marginals(Cathy.first);
+  DiscreteFactor::Values values;
+  values[Cathy.first] = 0;
+  EXPECT_DOUBLES_EQUAL( 1.944, (*actualC)(values), 1e-9);
+
+  Vector actualCvector = marginals.marginalProbabilities(Cathy.first);
+  EXPECT(assert_equal(Vector_(2,0.7,0.3), actualCvector, 1e-9));
+}
+
+/* ************************************************************************* */
+int main() {
+  TestResult tr;
+  return TestRegistry::runAllTests(tr);
+}
+/* ************************************************************************* */
+