Merge pull request #12025 from ThibHlln/patch-1

DOC: add detail for 'where' argument in ufunc

2 files changed, 12 insertions, 6 deletions

diff --git a/numpy/core/_add_newdocs.py b/numpy/core/_add_newdocs.py
index e5e7f6667..7a7a433c0 100644
--- a/numpy/core/_add_newdocs.py
+++ b/numpy/core/_add_newdocs.py
@@ -4618,10 +4618,12 @@ add_newdoc('numpy.core', 'ufunc',
         number of outputs; use `None` for uninitialized outputs to be
         allocated by the ufunc.
     where : array_like, optional
-        Values of True indicate to calculate the ufunc at that position, values
-        of False indicate to leave the value in the output alone.  Note that if
-        an uninitialized return array is created via the default ``out=None``,
-        then the elements where the values are False will remain uninitialized.
+        This condition is broadcast over the input. At locations where the
+        condition is True, the `out` array will be set to the ufunc result.
+        Elsewhere, the `out` array will retain its original value.
+        Note that if an uninitialized `out` array is created via the default
+        ``out=None``, locations within it where the condition is False will
+        remain uninitialized.
     **kwargs
         For other keyword-only arguments, see the :ref:`ufunc docs <ufuncs.kwargs>`.
 
diff --git a/numpy/core/code_generators/ufunc_docstrings.py b/numpy/core/code_generators/ufunc_docstrings.py
index 6a5def4f2..2a5646bd7 100644
--- a/numpy/core/code_generators/ufunc_docstrings.py
+++ b/numpy/core/code_generators/ufunc_docstrings.py
@@ -26,8 +26,12 @@ subst = {
             a freshly-allocated array is returned. A tuple (possible only as a
             keyword argument) must have length equal to the number of outputs.
         where : array_like, optional
-            Values of True indicate to calculate the ufunc at that position, values
-            of False indicate to leave the value in the output alone.
+            This condition is broadcast over the input. At locations where the
+            condition is True, the `out` array will be set to the ufunc result.
+            Elsewhere, the `out` array will retain its original value.
+            Note that if an uninitialized `out` array is created via the default
+            ``out=None``, locations within it where the condition is False will
+            remain uninitialized.
         **kwargs
             For other keyword-only arguments, see the
             :ref:`ufunc docs <ufuncs.kwargs>`.