2to3: Apply `map` fixer.

In Python 3 `map` is an iterator while in Python 2 it returns a list.
The simple fix applied by the fixer is to inclose all instances of map
with `list(...)`. This is not needed in all cases, and even where
appropriate list comprehensions may be preferred for their clarity.
Consequently, this patch attempts to use list comprehensions where it
makes sense.

When the mapped function has two arguments there is another problem that
can arise. In Python 3 map stops execution when the shortest argument
list is exhausted, while in Python 2 it stops when the longest argument
list is exhausted. Consequently the two argument case might need special
care. However, we have been running Python3 converted versions of numpy
since 1.5 without problems, so it is probably not something that affects
us.

Closes #3068

1 files changed, 2 insertions, 2 deletions

diff --git a/numpy/lib/stride_tricks.py b/numpy/lib/stride_tricks.py
index 5c9d222f3..1f08131ec 100644
--- a/numpy/lib/stride_tricks.py
+++ b/numpy/lib/stride_tricks.py
@@ -60,7 +60,7 @@ def broadcast_arrays(*args):
     Here is a useful idiom for getting contiguous copies instead of
     non-contiguous views.
 
-    >>> map(np.array, np.broadcast_arrays(x, y))
+    >>> [np.array(a) for a in np.broadcast_arrays(x, y)]
     [array([[1, 2, 3],
            [1, 2, 3],
            [1, 2, 3]]), array([[1, 1, 1],
@@ -68,7 +68,7 @@ def broadcast_arrays(*args):
            [3, 3, 3]])]
 
     """
-    args = map(np.asarray, args)
+    args = [np.asarray(_m) for _m in args]
     shapes = [x.shape for x in args]
     if len(set(shapes)) == 1:
         # Common case where nothing needs to be broadcasted.