From 7ce5b390be0568e090b1f01253f23eefbaf14ec7 Mon Sep 17 00:00:00 2001
From: Patrick Hoefler <61934744+phofl@users.noreply.github.com>
Date: Wed, 7 Sep 2022 20:08:16 +0200
Subject: [PATCH 1/2] Backport PR #48380: DOC: Clarify that objects dtype takes
 precedence in where

---
 doc/source/whatsnew/v1.5.0.rst | 1 +
 pandas/core/generic.py         | 3 +++
 2 files changed, 4 insertions(+)

diff --git a/doc/source/whatsnew/v1.5.0.rst b/doc/source/whatsnew/v1.5.0.rst
index c479c59082464..af0ba1bd75124 100644
--- a/doc/source/whatsnew/v1.5.0.rst
+++ b/doc/source/whatsnew/v1.5.0.rst
@@ -308,6 +308,7 @@ Other enhancements
 - Implemented a complex-dtype :class:`Index`, passing a complex-dtype array-like to ``pd.Index`` will now retain complex dtype instead of casting to ``object`` (:issue:`45845`)
 - :class:`Series` and :class:`DataFrame` with :class:`IntegerDtype` now supports bitwise operations (:issue:`34463`)
 - Add ``milliseconds`` field support for :class:`.DateOffset` (:issue:`43371`)
+- :meth:`DataFrame.where` tries to maintain dtype of :class:`DataFrame` if fill value can be cast without loss of precision (:issue:`45582`)
 - :meth:`DataFrame.reset_index` now accepts a ``names`` argument which renames the index names (:issue:`6878`)
 - :func:`concat` now raises when ``levels`` is given but ``keys`` is None (:issue:`46653`)
 - :func:`concat` now raises when ``levels`` contains duplicate values (:issue:`46653`)
diff --git a/pandas/core/generic.py b/pandas/core/generic.py
index 7b345a58bda88..080ee7ce9a4d0 100644
--- a/pandas/core/generic.py
+++ b/pandas/core/generic.py
@@ -9876,6 +9876,9 @@ def where(
         For further details and examples see the ``{name}`` documentation in
         :ref:`indexing <indexing.where_mask>`.
 
+        The dtype of the object takes precedence. The fill value is casted to
+        the objects dtype, if this can be done losslessly.
+
         Examples
         --------
         >>> s = pd.Series(range(5))

From 3b927f603e34fae20248b00d157d3c7c306991f8 Mon Sep 17 00:00:00 2001
From: Patrick Hoefler <61934744+phofl@users.noreply.github.com>
Date: Wed, 7 Sep 2022 22:43:46 +0200
Subject: [PATCH 2/2] Update generic.py

---
 pandas/core/generic.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/core/generic.py b/pandas/core/generic.py
index 080ee7ce9a4d0..20c5592071e2c 100644
--- a/pandas/core/generic.py
+++ b/pandas/core/generic.py
@@ -9877,7 +9877,7 @@ def where(
         :ref:`indexing <indexing.where_mask>`.
 
         The dtype of the object takes precedence. The fill value is casted to
-        the objects dtype, if this can be done losslessly.
+        the object's dtype, if this can be done losslessly.
 
         Examples
         --------