diff options
Diffstat (limited to 'numpy/core/fromnumeric.py')
| -rw-r--r-- | numpy/core/fromnumeric.py | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/numpy/core/fromnumeric.py b/numpy/core/fromnumeric.py index dae109a98..2b108bcf9 100644 --- a/numpy/core/fromnumeric.py +++ b/numpy/core/fromnumeric.py @@ -932,7 +932,27 @@ def diagonal(a, offset=0, axis1=0, axis2=1): removing `axis1` and `axis2` and appending an index to the right equal to the size of the resulting diagonals. - As of NumPy 1.7, this function always returns a view into `a`. + In versions of NumPy prior to 1.7, this function always returned a new, + independent array containing a copy of the values in the diagonal. + + In NumPy 1.7, it continues to return a copy of the diagonal, but depending + on this fact is deprecated. Writing to the resulting array continues to + work as it used to, but a DeprecationWarning will be issued. + + In NumPy 1.8, it will switch to returning a read-only view on the original + array. Attempting to write to the resulting array will produce an error. + + In NumPy 1.9, it will still return a view, but this view will no longer be + marked read-only. Writing to the returned array will alter your original + array as well. + + If you don't write to the array returned by this function, then you can + just ignore all of the above. + + If you depend on the current behavior, then we suggest copying the + returned array explicitly, i.e., use ``np.diagonal(a).copy()`` instead of + just ``np.diagonal(a)``. This will work with both past and future versions + of NumPy. Parameters ---------- |