Fix type problem when in dimension 0.

tensor.py

@@ -1041,7 +1041,7 @@ class Dot(Op):
         return Apply(self, inputs, outputs)
 
     def perform(self, node, (x, y), (z, )):
-        z[0] = numpy.dot(x, y)
+        z[0] = numpy.asarray(numpy.dot(x, y))
     def grad(self, (x, y), (gz,)):
         if gz.type.ndim == 0:
             return gz * y, gz * x