Simply sum-product test in Python.

python/gtsam/tests/test_DiscreteFactorGraph.py

@@ -14,7 +14,7 @@
 import unittest
 
 import numpy as np
-from gtsam import DiscreteConditional, DiscreteFactorGraph, DiscreteKeys, DiscreteValues, Ordering, Symbol
+from gtsam import DecisionTreeFactor, DiscreteConditional, DiscreteFactorGraph, DiscreteKeys, DiscreteValues, Ordering, Symbol
 from gtsam.utils.test_case import GtsamTestCase
 
 OrderingType = Ordering.OrderingType
@@ -250,7 +250,7 @@ def make_key(character, index, cardinality):
 
         # Ensure that the stationary distribution is positive and normalized
         stationary_dist /= np.sum(stationary_dist)
-        expected = stationary_dist.flatten()
+        expected = DecisionTreeFactor(X[chain_length-1], stationary_dist.flatten())
 
         # The transition matrix parsed by DiscreteConditional is a row-wise CPT
         transitions = transitions.T
@@ -271,16 +271,8 @@ def make_key(character, index, cardinality):
         # Get the DiscreteConditional representing the marginal on the last factor
         last_marginal = sum_product.at(chain_length - 1)
 
-        # Extract the actual marginal probabilities
-        assignment = DiscreteValues()
-        marginal_probs = []
-        for i in range(num_states):
-            assignment[X[chain_length - 1][0]] = i
-            marginal_probs.append(last_marginal(assignment))
-        marginal_probs = np.array(marginal_probs)
-
         # Ensure marginal probabilities are close to the stationary distribution
-        self.gtsamAssertEquals(expected, marginal_probs)
+        self.gtsamAssertEquals(expected, last_marginal)
 
 if __name__ == "__main__":
     unittest.main()