public virtual void TestSumOut(TableFactor factor, int marginalize) { if (!Arrays.Stream(factor.neighborIndices).Boxed().Collect(Collectors.ToSet()).Contains(marginalize)) { return; } if (factor.neighborIndices.Length <= 1) { return; } TableFactor summedOut = factor.SumOut((int)marginalize); NUnit.Framework.Assert.AreEqual(factor.neighborIndices.Length - 1, summedOut.neighborIndices.Length); NUnit.Framework.Assert.IsTrue(!Arrays.Stream(summedOut.neighborIndices).Boxed().Collect(Collectors.ToSet()).Contains(marginalize)); IDictionary<IList<int>, IList<int[]>> subsetToSuperset = SubsetToSupersetAssignments((TableFactor)factor, summedOut); foreach (IList<int> subsetAssignmentList in subsetToSuperset.Keys) { double sum = 0.0; foreach (int[] supersetAssignment in subsetToSuperset[subsetAssignmentList]) { sum += factor.GetAssignmentValue(supersetAssignment); } int[] subsetAssignment = new int[subsetAssignmentList.Count]; for (int i = 0; i < subsetAssignment.Length; i++) { subsetAssignment[i] = subsetAssignmentList[i]; } NUnit.Framework.Assert.AreEqual(summedOut.GetAssignmentValue(subsetAssignment), 1.0e-5, sum); } }
/// <summary>This is a key step in message passing.</summary> /// <remarks> /// This is a key step in message passing. When we are calculating a message, we want to marginalize out all variables /// not relevant to the recipient of the message. This function does that. /// </remarks> /// <param name="message">the message to marginalize</param> /// <param name="relevant">the variables that are relevant</param> /// <param name="marginalize">whether to use sum of max marginalization, for marginal or MAP inference</param> /// <returns>the marginalized message</returns> private static TableFactor MarginalizeMessage(TableFactor message, int[] relevant, CliqueTree.MarginalizationMethod marginalize) { TableFactor result = message; foreach (int i in message.neighborIndices) { bool contains = false; foreach (int j in relevant) { if (i == j) { contains = true; break; } } if (!contains) { switch (marginalize) { case CliqueTree.MarginalizationMethod.Sum: { result = result.SumOut(i); break; } case CliqueTree.MarginalizationMethod.Max: { result = result.MaxOut(i); break; } } } } return(result); }
private void CheckMarginalsAgainstBruteForce(GraphicalModel model, ConcatVector weights, CliqueTree inference) { CliqueTree.MarginalResult result = inference.CalculateMarginals(); double[][] marginals = result.marginals; ICollection <TableFactor> tableFactors = model.factors.Stream().Map(null).Collect(Collectors.ToSet()); System.Diagnostics.Debug.Assert((tableFactors.Count == model.factors.Count)); // this is the super slow but obviously correct way to get global marginals TableFactor bruteForce = null; foreach (TableFactor factor in tableFactors) { if (bruteForce == null) { bruteForce = factor; } else { bruteForce = bruteForce.Multiply(factor); } } if (bruteForce != null) { // observe out all variables that have been registered TableFactor observed = bruteForce; for (int i = 0; i < bruteForce.neighborIndices.Length; i++) { int n = bruteForce.neighborIndices[i]; if (model.GetVariableMetaDataByReference(n).Contains(CliqueTree.VariableObservedValue)) { int value = System.Convert.ToInt32(model.GetVariableMetaDataByReference(n)[CliqueTree.VariableObservedValue]); // Check that the marginals reflect the observation for (int j = 0; j < marginals[n].Length; j++) { NUnit.Framework.Assert.AreEqual(marginals[n][j], 1.0e-9, j == value ? 1.0 : 0.0); } if (observed.neighborIndices.Length > 1) { observed = observed.Observe(n, value); } else { // If we've observed everything, then just quit return; } } } bruteForce = observed; // Spot check each of the marginals in the brute force calculation double[][] bruteMarginals = bruteForce.GetSummedMarginals(); int index = 0; foreach (int i_1 in bruteForce.neighborIndices) { bool isEqual = true; double[] brute = bruteMarginals[index]; index++; System.Diagnostics.Debug.Assert((brute != null)); System.Diagnostics.Debug.Assert((marginals[i_1] != null)); for (int j = 0; j < brute.Length; j++) { if (double.IsNaN(brute[j])) { isEqual = false; break; } if (Math.Abs(brute[j] - marginals[i_1][j]) > 3.0e-2) { isEqual = false; break; } } if (!isEqual) { System.Console.Error.WriteLine("Arrays not equal! Variable " + i_1); System.Console.Error.WriteLine("\tGold: " + Arrays.ToString(brute)); System.Console.Error.WriteLine("\tResult: " + Arrays.ToString(marginals[i_1])); } Assert.AssertArrayEquals(marginals[i_1], 3.0e-2, brute); } // Spot check the partition function double goldPartitionFunction = bruteForce.ValueSum(); // Correct to within 3% NUnit.Framework.Assert.AreEqual(result.partitionFunction, goldPartitionFunction * 3.0e-2, goldPartitionFunction); // Check the joint marginals foreach (GraphicalModel.Factor f in model.factors) { NUnit.Framework.Assert.IsTrue(result.jointMarginals.Contains(f)); TableFactor bruteForceJointMarginal = bruteForce; foreach (int n in bruteForce.neighborIndices) { foreach (int i_2 in f.neigborIndices) { if (i_2 == n) { goto outer_continue; } } if (bruteForceJointMarginal.neighborIndices.Length > 1) { bruteForceJointMarginal = bruteForceJointMarginal.SumOut(n); } else { int[] fixedAssignment = new int[f.neigborIndices.Length]; for (int i_3 = 0; i_3 < fixedAssignment.Length; i_3++) { fixedAssignment[i_3] = System.Convert.ToInt32(model.GetVariableMetaDataByReference(f.neigborIndices[i_3])[CliqueTree.VariableObservedValue]); } foreach (int[] assn in result.jointMarginals[f]) { if (Arrays.Equals(assn, fixedAssignment)) { NUnit.Framework.Assert.AreEqual(result.jointMarginals[f].GetAssignmentValue(assn), 1.0e-7, 1.0); } else { if (result.jointMarginals[f].GetAssignmentValue(assn) != 0) { TableFactor j = result.jointMarginals[f]; foreach (int[] assignment in j) { System.Console.Error.WriteLine(Arrays.ToString(assignment) + ": " + j.GetAssignmentValue(assignment)); } } NUnit.Framework.Assert.AreEqual(result.jointMarginals[f].GetAssignmentValue(assn), 1.0e-7, 0.0); } } goto marginals_continue; } } outer_break :; // Find the correspondence between the brute force joint marginal, which may be missing variables // because they were observed out of the table, and the output joint marginals, which are always an exact // match for the original factor int[] backPointers = new int[f.neigborIndices.Length]; int[] observedValue = new int[f.neigborIndices.Length]; for (int i_4 = 0; i_4 < backPointers.Length; i_4++) { if (model.GetVariableMetaDataByReference(f.neigborIndices[i_4]).Contains(CliqueTree.VariableObservedValue)) { observedValue[i_4] = System.Convert.ToInt32(model.GetVariableMetaDataByReference(f.neigborIndices[i_4])[CliqueTree.VariableObservedValue]); backPointers[i_4] = -1; } else { observedValue[i_4] = -1; backPointers[i_4] = -1; for (int j = 0; j < bruteForceJointMarginal.neighborIndices.Length; j++) { if (bruteForceJointMarginal.neighborIndices[j] == f.neigborIndices[i_4]) { backPointers[i_4] = j; } } System.Diagnostics.Debug.Assert((backPointers[i_4] != -1)); } } double sum = bruteForceJointMarginal.ValueSum(); if (sum == 0.0) { sum = 1; } foreach (int[] assignment_1 in result.jointMarginals[f]) { int[] bruteForceMarginalAssignment = new int[bruteForceJointMarginal.neighborIndices.Length]; for (int i_2 = 0; i_2 < assignment_1.Length; i_2++) { if (backPointers[i_2] != -1) { bruteForceMarginalAssignment[backPointers[i_2]] = assignment_1[i_2]; } else { // Make sure all assignments that don't square with observations get 0 weight System.Diagnostics.Debug.Assert((observedValue[i_2] != -1)); if (assignment_1[i_2] != observedValue[i_2]) { if (result.jointMarginals[f].GetAssignmentValue(assignment_1) != 0) { System.Console.Error.WriteLine("Joint marginals: " + Arrays.ToString(result.jointMarginals[f].neighborIndices)); System.Console.Error.WriteLine("Assignment: " + Arrays.ToString(assignment_1)); System.Console.Error.WriteLine("Observed Value: " + Arrays.ToString(observedValue)); foreach (int[] assn in result.jointMarginals[f]) { System.Console.Error.WriteLine("\t" + Arrays.ToString(assn) + ":" + result.jointMarginals[f].GetAssignmentValue(assn)); } } NUnit.Framework.Assert.AreEqual(result.jointMarginals[f].GetAssignmentValue(assignment_1), 1.0e-7, 0.0); goto outer_continue; } } } NUnit.Framework.Assert.AreEqual(result.jointMarginals[f].GetAssignmentValue(assignment_1), 1.0e-3, bruteForceJointMarginal.GetAssignmentValue(bruteForceMarginalAssignment) / sum); } outer_break :; } marginals_break :; } else { foreach (double[] marginal in marginals) { foreach (double d in marginal) { NUnit.Framework.Assert.AreEqual(d, 3.0e-2, 1.0 / marginal.Length); } } } }