DOC: Update documentation for isfortran.

Clarify isfortran checks if an array is both Fortran contiguous and
*not* C contiguous. The suggests that it only checks if the array is F
contiguous, but that is not the case.

1 files changed, 6 insertions, 2 deletions

diff --git a/numpy/core/numeric.py b/numpy/core/numeric.py
index 5c0e27239..4350e123f 100644
--- a/numpy/core/numeric.py
+++ b/numpy/core/numeric.py
@@ -696,8 +696,12 @@ def require(a, dtype=None, requirements=None):
 
 def isfortran(a):
     """
-    Returns True if array is arranged in Fortran-order in memory
-    and not C-order.
+    Returns True if the array is Fortran contiguous but *not* C contiguous.
+
+    This function is obsolete and, because of changes due to relaxed stride
+    checking, its return value for the same array may differ for versions
+    of Numpy >= 1.10 and previous versions. If you only want to check if an
+    array is Fortran contiguous use ``a.flags.f_contiguous`` instead.
 
     Parameters
     ----------