Removed all class-member initialization from MRG_RandomStreams, RandomStreams

theano/sandbox/test_rng_mrg.py

@@ -680,20 +680,12 @@ class T_MRG(unittest.TestCase):
 
 def test_multiple_rng():
     """
-    Test that we can have multiple random number generators in parallel, and
-    that we can replicate the stream of one with another. This is meant to fix a
-    previous bug in rng_mrg.MRG_RandomStreams where state_updates was
-    initialized as a class variable, instead of in the __init__ method. This
-    would cause all MRG_RandomStreams objects to share the same state.
+    Test that when we have multiple random number generators, we do not alias
+    the state_updates member. `state_updates` can be useful when attempting to
+    copy the (random) state between two similar theano graphs. The test is
+    meant to detect a previous bug where state_updates was initialized as a
+    class-attribute, instead of the __init__ function.
     """
     rng1 = MRG_RandomStreams(1234)
-    var1 = theano.shared(numpy.ones(1))
-    out1 = rng1.uniform(size=(1,))
-    f1 = theano.function([], out1, updates={var1: out1})
-    assert len(rng1.state_updates) == 1
-    
-    rng2 = MRG_RandomStreams(1234)
-    out2 = rng2.uniform(size=(1,))
-    f2 = theano.function([], out2, updates={var1: out2})
-    assert len(rng1.state_updates) == 1
-    assert len(rng2.state_updates) == 1
+    rng2 = MRG_RandomStreams(2392)
+    assert rng1.state_updates is not rng2.state_updates

theano/tensor/randomstreams.py

@@ -122,20 +122,6 @@ class RandomStreams(Component, raw_random.RandomStreamsBase):
 
     """
 
-    random_state_variables = []
-    """A list of pairs of the form (input_r, output_r).  This will be
-    over-ridden by the module instance to contain stream
-    generators.
-
-    """
-
-    default_instance_seed = None
-    """Instance variable should take None or integer value.  Used to
-    seed the random number generator that provides seeds for member
-    streams
-
-    """
-
     def __init__(self, seed=None, no_warn=False):
         """:type seed: None or int
 
@@ -147,7 +133,13 @@ class RandomStreams(Component, raw_random.RandomStreamsBase):
         if not no_warn:
             deprecation_warning()
         super(RandomStreams, self).__init__(no_warn=True)
+
+        # A list of pairs of the form (input_r, output_r).  This will be
+        # over-ridden by the module instance to contain stream generators.
         self.random_state_variables = []
+
+        # Instance variable should take None or integer value.  Used to seed the
+        # random number generator that provides seeds for member streams
         self.default_instance_seed = seed
 
     def allocate(self, memo):

theano/tensor/tests/test_randomstreams.py

@@ -682,6 +682,17 @@ class T_RandomStreams(unittest.TestCase):
         assert val1.dtype == 'int8'
         assert numpy.all(abs(val1) <= 1)
 
+    def test_multiple_rng(self):
+        """
+        Test that when we have multiple random number generators, we do not alias
+        the state_updates member. `state_updates` can be useful when attempting to
+        copy the (random) state between two similar theano graphs. The test is
+        meant to detect a previous bug where state_updates was initialized as a
+        class-attribute, instead of the __init__ function.
+        """
+        rng1 = RandomStreams(1234)
+        rng2 = RandomStreams(2392)
+        assert rng1.random_state_variables is not rng2.random_state_variables
 
 if __name__ == '__main__':
     from theano.tests import main

theano/tensor/tests/test_shared_randomstreams.py

@@ -715,7 +715,18 @@ class T_SharedRandomStreams(unittest.TestCase):
         s_rng.set_value(rr, borrow=True)
         assert rr is s_rng.container.storage[0]
 
-
+    def test_multiple_rng(self):
+        """
+        Test that when we have multiple random number generators, we do not alias
+        the state_updates member. `state_updates` can be useful when attempting to
+        copy the (random) state between two similar theano graphs. The test is
+        meant to detect a previous bug where state_updates was initialized as a
+        class-attribute, instead of the __init__ function.
+        """
+        rng1 = RandomStreams(1234)
+        rng2 = RandomStreams(2392)
+        assert rng1.state_updates is not rng2.state_updates
+        assert rng1.gen_seedgen is not rng2.gen_seedgen
 
 
 if __name__ == '__main__':