Merge pull request #1521 from nouiz/fix_tutorial_int32

doc/tutorial/examples.txt

@@ -254,10 +254,11 @@ for the purpose of one particular function.
 .. theano/tests/test_tutorial.py:T_examples.test_examples_8
 
 >>> fn_of_state = state * 2 + inc
->>> foo = T.iscalar()  # the type (lscalar) must match the shared variable we
->>>                    # are replacing with the ``givens`` list
+>>> # The type of foo must match the shared variable we are replacing
+>>> # with the ``givens``
+>>> foo = T.scalar(dtype=state.dtype)
 >>> skip_shared = function([inc, foo], fn_of_state,
-        givens=[(state, foo)])
+                           givens=[(state, foo)])
 >>> skip_shared(1, 3)  # we're using 3 for the state, not state.value
 array(7)
 >>> state.get_value()  # old state still there, but we didn't use it

doc/tutorial/printing_drawing.txt

@@ -19,9 +19,13 @@ The following output depicts the pre- and post- compilation graphs.
 
 .. code-block:: python
     
-    import numpy
     import theano
     import theano.tensor as T
+
+    import numpy
+
+    import os
+
     rng = numpy.random
 
     N = 400
@@ -52,16 +56,16 @@ The following output depicts the pre- and post- compilation graphs.
     train = theano.function(
                 inputs=[x, y],
                 outputs=[prediction, xent],
-                updates={w: w - 0.01 * gw, b: b - 0.01 * gb},
+                updates=[(w, w - 0.01 * gw), (b, b - 0.01 * gb)],
                 name="train")
     predict = theano.function(inputs=[x], outputs=prediction,
                 name="predict")
 
-    if any( [x.op.__class__.__name__=='Gemv' for x in
-    train.maker.fgraph.toposort()]):
+    if any([x.op.__class__.__name__ in ['Gemv', 'CGemv'] for x in
+            train.maker.fgraph.toposort()]):
         print 'Used the cpu'
-    elif any( [x.op.__class__.__name__=='GpuGemm' for x in
-    train.maker.fgraph.toposort()]):
+    elif any([x.op.__class__.__name__ == 'GpuGemm' for x in
+             train.maker.fgraph.toposort()]):
         print 'Used the gpu'
     else:
         print 'ERROR, not able to tell if theano used the cpu or the gpu'
@@ -82,6 +86,8 @@ The following output depicts the pre- and post- compilation graphs.
 
     # Print the picture graphs
     # after compilation
+    if not os.path.exists('pics'):
+        os.mkdir('pics')
     theano.printing.pydotprint(predict,
                                outfile="pics/logreg_pydotprint_predic.png",
                                var_with_name_simple=True)

theano/printing.py

@@ -957,8 +957,21 @@ def pydotprint_variables(vars,
     for nd in vars:
         if nd.owner:
             plot_apply(nd.owner, depth)
-
-    g.write_png(outfile, prog='dot')
+    try:
+        g.write_png(outfile, prog='dot')
+    except pd.InvocationException, e:
+        # Some version of pydot are bugged/don't work correctly with
+        # empty label. Provide a better user error message.
+        if pd.__version__ == "1.0.28" and "label=]" in e.message:
+            raise Exception("pydot 1.0.28 is know to be bugged. Use another "
+                            "working version of pydot")
+        elif "label=]" in e.message:
+            raise Exception("Your version of pydot " + pd.__version__ +
+                            " returned an error. Version 1.0.28 is known"
+                            " to be bugged and 1.0.25 to be working with"
+                            " Theano. Using another version of pydot could"
+                            " fix this problem. The pydot error is: " +
+                            e.message)
 
     print 'The output file is available at', outfile
 

theano/tests/test_tutorial.py

@@ -585,7 +585,7 @@ class T_examples(unittest.TestCase):
         from theano import shared
         # Force the dtype to int64 to work correctly on 32 bit computer.
         # Otherwise, it create by default a int32 on 32 bit computer.
-        state = shared(numpy.int64(0))
+        state = shared(0)
         inc = T.iscalar('inc')
         accumulator = function([inc], state, updates=[(state, state+inc)])
 
@@ -604,10 +604,11 @@ class T_examples(unittest.TestCase):
         assert state.get_value()       == array(0)
 
         fn_of_state = state * 2 + inc
-        foo = T.lscalar()    # the type (lscalar) must match the shared variable we
-                            # are replacing with the ``givens`` list
+        # The type of foo must match the shared variable we are replacing
+        # with the ``givens``
+        foo = T.scalar(dtype=state.dtype)
         skip_shared = function([inc, foo], fn_of_state,
-                                                givens=[(state, foo)])
+                               givens=[(state, foo)])
         assert skip_shared(1, 3)       == array(7)
         assert state.get_value()       == array(0)