easy factorelimination

primo/reasoning/density/ProbabilityTable.py

@@ -173,6 +173,26 @@ class ProbabilityTable(Density):
             reduced.variables.remove(node)
 
         return reduced
+        
+    def set_evidence(self,evidence):     
+        '''Returns a new version of the ProbabilityTable with only the evidence
+        not equal zero'''
+        
+        ev = ProbabilityTable()
+        ev.variables = copy.copy(self.variables)
+        ev.table = numpy.zeros(self.table.shape) 
+        tmpCpd = self.table
+        
+        pos_variable = ev.variables.index(evidence[0])
+        pos_value = ev.variables[pos_variable].value_range.index(evidence[1])
+        
+        ev.table = numpy.rollaxis(ev.table,pos_variable,0)
+        tmpCpd = numpy.rollaxis(tmpCpd,pos_variable,0)
+        ev.variables.insert(0,ev.variables.pop(pos_variable))
+
+        ev.table[pos_value] = tmpCpd[pos_value]
+
+        return ev
 
 
 

primo/reasoning/factorelemination/EasiestFactorElimination.py

@@ -31,10 +31,59 @@ class EasiestFactorElimination(object):
         return finCpd
         
     def calculate_PosteriorMarginal(self,variables,evidence):
-        bn = bn.copy()
+        #TODO
+        # Verbundwahrscheinlichkeit / PoE
+        # Erst wie Prior Marginal nur mit setzen der Evidence
+        # Dann PoE berechnen und damit normalisieren
+        nodes = self.bn.get_all_nodes()
         
+        unzipped_list = zip(*evidence)
+              
+        node1 = nodes.pop()
+        if node1 in unzipped_list[0]:
+            ind = unzipped_list[0].index(node1)
+            finCpd = node1.get_cpd().set_evidence(evidence[ind])
+            
+        else:
+            finCpd = node1.get_cpd()
+                  
+        for n in nodes:
+            if n in unzipped_list[0]:
+                ind = unzipped_list[0].index(n)
+                nCPD = n.get_cpd().set_evidence(evidence[ind])
+                finCpd = finCpd.multiplication(nCPD)
+            else:
+                finCpd = finCpd.multiplication(n.get_cpd())
+          
+        for v in finCpd.get_variables()[:]:
+            finCpd = finCpd.marginalization(v)
+            
+        return finCpd
         
-    def calculate_PoE(self,evidence):
-        bn = bn.copy()
         
         
+    def calculate_PoE(self,evidence):
+        nodes = self.bn.get_all_nodes()
+        
+        unzipped_list = zip(*evidence)
+              
+        node1 = nodes.pop()
+        if node1 in unzipped_list[0]:
+            ind = unzipped_list[0].index(node1)
+            finCpd = node1.get_cpd().set_evidence(evidence[ind])
+            
+        else:
+            finCpd = node1.get_cpd()
+                  
+        for n in nodes:
+            if n in unzipped_list[0]:
+                ind = unzipped_list[0].index(n)
+                nCPD = n.get_cpd().set_evidence(evidence[ind])
+                finCpd = finCpd.multiplication(nCPD)
+            else:
+                finCpd = finCpd.multiplication(n.get_cpd())
+          
+        for v in finCpd.get_variables()[:]:
+            finCpd = finCpd.marginalization(v)
+            
+        return finCpd