made functiongraph more deterministic

theano/gof/fg.py

@@ -12,6 +12,9 @@ from python25 import all
 from theano import config
 import warnings
 NullType = None
+import theano
+from python25 import OrderedDict
+from theano.misc.ordered_set import OrderedSet
 
 class InconsistencyError(Exception):
     """
@@ -553,10 +556,44 @@ class FunctionGraph(utils.object2):
             # 1-element graphs.
             return list(self.apply_nodes)
         fg = self
+        if verbose:
+            print 'FunctionGraph.toposort multinode'
 
+        # DEBUGGING NOTE: this might be the source of non-determinism.
+        #                 it definitely contains dicts and lists made
+        #                 by iterating over dicts.
+        #                 does it affect the final sort order though?
         ords = self.orderings()
 
+        if verbose:
+            """
+            print 'FunctionGraph inputs'
+            assert isinstance(fg.inputs, list)
+            for i, elem in enumerate(fg.inputs):
+                print '\t%d:' % i
+                print theano.printing.min_informative_str(elem, indent_level=1)
+            print 'FunctionGraph outputs'
+            assert isinstance(fg.outputs, list)
+            for i, elem in enumerate(fg.outputs):
+                print '\t%d:' % i
+                print theano.printing.min_informative_str(elem, indent_level=1)
+            """
+            for i, key in enumerate(ords):
+                print 'orderings',i
+                print '\tkey',i,'is',key
+                v = ords[key]
+                print '\t\tvalue',i,'is a',type(v)
+                for j, elem in enumerate(v):
+                    print '\t\t\telem',j,':',elem
+
+
+
         order = graph.io_toposort(fg.inputs, fg.outputs, ords)
+
+        if verbose:
+            print 'FunctionGraph.toposort returning order:'
+            for i, elem in enumerate(order):
+                print '\t%d:'%i,elem
         return order
 
     def orderings(self):
@@ -571,14 +608,19 @@ class FunctionGraph(utils.object2):
                take care of computing dependencies by itself.
 
         """
-        ords = {}
+        ords =  OrderedDict()
+        assert isinstance(self._features, list)
         for feature in self._features:
             if hasattr(feature, 'orderings'):
-                for node, prereqs in feature.orderings(self).items():
+                orderings = feature.orderings(self)
+                if not isinstance(orderings, OrderedDict):
+                    raise TypeError("Non-deterministic return value from " \
+                            +str(feature.orderings) \
+                            +". Nondeterministic object is "+str(orderings))
                     ords.setdefault(node, []).extend(prereqs)
         # eliminate duplicate prereqs
         for (node,prereqs) in ords.items():
-            ords[node] = list(set(prereqs))
+            ords[node] = list(OrderedSet(prereqs))
         return ords
 
     def nclients(self, r):