Merge pull request #2953 from nouiz/small

doc/install_ubuntu.txt

@@ -179,9 +179,10 @@ Manual Openblas instruction
     I believe this is outdated, my machine seems to be using 8 threads 
     happily with the binary openblas...
 
-The openblas included in Ubuntu is limited to 2 threads. If you want
-to use more cores at the same time, you will need to compile it
-yourself. Here is some code that will help you.
+The openblas included in some older Ubuntu version is limited to 2
+threads. Ubuntu 14.04 do not have this limit. If you want to use more
+cores at the same time, you will need to compile it yourself. Here is
+some code that will help you.
 
 .. code-block:: bash
 

theano/gof/opt.py

@@ -1499,7 +1499,8 @@ class NavigatorOptimizer(Optimizer):
             replacements = replacements.values()
         elif not isinstance(replacements, (tuple, list)):
             raise TypeError('Optimizer %s gave wrong type of replacement. '
-                            'Expected list or tuple.' % lopt)
+                            'Expected list or tuple. Got %s' % (
+                                lopt, replacements))
         if len(old_vars) != len(replacements):
             raise ValueError('Optimizer %s gave wrong number of replacements'
                              % lopt)

theano/sandbox/cuda/cuda_ndarray.cu

@@ -307,7 +307,7 @@ static size_t work_size = 0;
  * request a single chunk of memory at a time since it is reused.
  */
 void *get_work_mem(size_t sz) {
-    if (sz < work_size)
+    if (sz <= work_size)
         return work_mem;
     device_free(work_mem);
     work_mem = device_malloc(sz);