diff options
Diffstat (limited to 'doc/source/reference')
| -rw-r--r-- | doc/source/reference/ufuncs.rst | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/doc/source/reference/ufuncs.rst b/doc/source/reference/ufuncs.rst index 8f506dd8b..a0a5a4a06 100644 --- a/doc/source/reference/ufuncs.rst +++ b/doc/source/reference/ufuncs.rst @@ -335,6 +335,19 @@ advanced usage and will not typically be used. Note that outputs not explicitly filled are left with their uninitialized values. + .. versionadded:: 1.13 + + Operations where ufunc input and output operands have memory overlap are + defined to be the same as for equivalent operations where there + is no memory overlap. Operations affected make temporary copies + as needed to eliminate data dependency. As detecting these cases + is computationally expensive, a heuristic is used, which may in rare + cases result in needless temporary copies. For operations where the + data dependency is simple enough for the heuristic to analyze, + temporary copies will not be made even if the arrays overlap, if it + can be deduced copies are not necessary. As an example, + ``np.add(a, b, out=a)`` will not involve copies. + *where* .. versionadded:: 1.7 |