Added normalization for sum units.

src/probabilistic_model/__init__.py

@@ -1 +1 @@
-__version__ = "3.3.3"
+__version__ = "3.3.4"

src/probabilistic_model/probabilistic_circuit/probabilistic_circuit.py

@@ -724,6 +724,14 @@ def simplify(self) -> Self:
 
         return result
 
+    def normalize(self):
+        """
+        Normalize the weights of the subcircuits such that they sum up to 1 inplace.
+        """
+        total_weight = sum([weight for weight, _ in self.weighted_subcircuits])
+        for subcircuit in self.subcircuits:
+            self.probabilistic_circuit.edges[self, subcircuit]["weight"] /= total_weight
+
 
 class DeterministicSumUnit(SmoothSumUnit):
     """

test/test_probabilistic_circuits/test_graph_circuit.py

@@ -486,5 +486,20 @@ def test_simplify(self):
         self.assertEqual(len(simplified.probabilistic_circuit.nodes()), len(self.model.probabilistic_circuit.nodes))
         self.assertEqual(len(simplified.probabilistic_circuit.edges()), len(self.model.probabilistic_circuit.edges))
 
+
+class NormalizationTestCase(unittest.TestCase):
+    x: Continuous = Continuous("x")
+
+    def test_normalization(self):
+        u1 = UniformDistribution(self.x, portion.closed(0, 1))
+        u2 = UniformDistribution(self.x, portion.closed(3, 4))
+        sum_unit = DeterministicSumUnit()
+        sum_unit.add_subcircuit(u1, 0.5)
+        sum_unit.add_subcircuit(u2, 0.3)
+        sum_unit.normalize()
+        self.assertAlmostEqual(sum_unit.weights[0], 0.5/0.8)
+        self.assertAlmostEqual(sum_unit.weights[1], 0.3/0.8)
+
+
 if __name__ == '__main__':
     unittest.main()