Fixed typo which was causing an error (undefined variable). Please test before

theano/compile/debugmode.py

@@ -865,7 +865,6 @@ class _Linker(gof.link.LocalLinker):
                         for r in node.outputs:
                             if not r.type.is_valid_value(storage_map[r][0]):
                                 raise InvalidValueError(r, storage_map[r][0])
-                            #if r in r_vals:
 
                         _check_inputs(node, storage_map, r_vals, dr_vals, active_order_set,
                                 clobber_dr_vals=True)

theano/scalar/basic.py

@@ -648,7 +648,7 @@ class First(BinaryScalarOp):
     def c_code(self, node, name, (x, y), (z, ), sub):
         return "%(z)s = %(x)s;" % locals()
     def grad(self, (x, y), (gz, )):
-        return gz if x.type in grad_type else None, None
+        return gz if x.type in grad_types else None, None
 first = First(transfer_type(0), name = 'first')
 
 class Second(BinaryScalarOp):
@@ -668,7 +668,7 @@ class Identity(UnaryScalarOp):
     def c_code(self, node, name, (x, ), (z, ), sub):
         return "%(z)s = %(x)s;" % locals()
     def grad(self, (x, ), (gz, )):
-        return gz if x.type in grad_type else None,
+        return gz if x.type in grad_types else None,
 identity = Identity(same_out, name = 'identity')
 
 class Abs(UnaryScalarOp):

theano/tensor/randomstreams.py

@@ -172,3 +172,15 @@ class RandomStreams(Component):
         """
         return self.gen(raw_random.random_integers, *args, **kwargs)
 
+
+randstream_singleton = []
+
+def getRandomStream(seed=None, force_new=False):
+    global randstream_singleton
+    if force_new or not randstream_singleton:
+        print 'creating random stream with seed %i' % seed
+        randstream_singleton = []
+        randstream_singleton.append(RandomStreams(seed))
+    elif seed:
+        print >> sys.stderr, 'Warning: RandomStream singleton already instantiated. Seed %i will be ignored'%seed
+    return randstream_singleton[0]

theano/tensor/tests/test_randomstreams.py

@@ -3,10 +3,10 @@ __docformat__ = "restructuredtext en"
 import sys
 import unittest
 import numpy 
-
-from theano.tensor.randomstreams import RandomStreams, raw_random
+from theano.tensor.randomstreams import RandomStreams, raw_random, getRandomStream, randstream_singleton
 from theano.compile import Module, Method, Member
 
+import theano
 from theano import tensor
 from theano import compile, gof
 
@@ -139,6 +139,40 @@ class T_RandomStreams(unittest.TestCase):
 
 
 
+    def test_singleton(self):
+
+        moda = Module()
+        moda.randa = getRandomStream(12)
+        a = moda.randa.uniform((2,2))
+        moda.fn = Method([], a)
+        imoda = moda.make()
+        imoda.randa.initialize()
+
+        modb = Module()
+        modb.randb = getRandomStream()
+        b = modb.randb.uniform((2,2))
+        modb.fn = Method([], b)
+        imodb = modb.make()
+        imodb.randb.initialize()
+
+        avals1 = imoda.fn()
+        bvals1 = imodb.fn()
+       
+        modc = Module()
+        modc.randc = getRandomStream(12, force_new=True)
+        a2 = modc.randc.uniform((2,2))
+        b2 = modc.randc.uniform((2,2))
+        modc.fna = Method([], a2)
+        modc.fnb = Method([], b2)
+        imodc = modc.make()
+        imodc.randc.initialize()
+
+        avals2 = imodc.fna()
+        bvals2 = imodc.fnb()
+
+        assert (avals1 == avals2).all()
+        assert (bvals1 == bvals2).all()
+
 if __name__ == '__main__':
     from theano.tests import main
     main("test_randomstreams")