From fde5ed8e4078a4b59fa2889a882b27684f89b506 Mon Sep 17 00:00:00 2001
From: SaraInCode <42293506+SaraInCode@users.noreply.github.com>
Date: Sun, 23 Feb 2025 10:50:51 +0100
Subject: [PATCH 1/4] Updated set_index doc with a warning

---
 pandas/core/frame.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/pandas/core/frame.py b/pandas/core/frame.py
index 3199733cfb85f..7393dd748542e 100644
--- a/pandas/core/frame.py
+++ b/pandas/core/frame.py
@@ -5868,6 +5868,10 @@ def set_index(
         columns or arrays (of the correct length). The index can replace the
         existing index or expand on it.
 
+        .. warning::
+            Setting a new index will remove the current index column,
+            unless you first call `reset_index`.
+
         Parameters
         ----------
         keys : label or array-like or list of labels/arrays

From fa65ba5d0f1eb7fb519c8f2eea9786fef3202b30 Mon Sep 17 00:00:00 2001
From: SaraInCode <42293506+SaraInCode@users.noreply.github.com>
Date: Sun, 2 Mar 2025 11:10:23 +0100
Subject: [PATCH 2/4] Updated set_index parameter append along with an example

---
 pandas/core/frame.py | 25 +++++++++++++++++++++----
 1 file changed, 21 insertions(+), 4 deletions(-)

diff --git a/pandas/core/frame.py b/pandas/core/frame.py
index 82989e9a3904d..b9e28395d9092 100644
--- a/pandas/core/frame.py
+++ b/pandas/core/frame.py
@@ -5868,10 +5868,6 @@ def set_index(
         columns or arrays (of the correct length). The index can replace the
         existing index or expand on it.
 
-        .. warning::
-            Setting a new index will remove the current index column,
-            unless you first call `reset_index`.
-
         Parameters
         ----------
         keys : label or array-like or list of labels/arrays
@@ -5884,6 +5880,8 @@ def set_index(
             Delete columns to be used as the new index.
         append : bool, default False
             Whether to append columns to existing index.
+            Setting to True will add the new columns to existing index.
+            When set to False, the current index will be dropped from the DataFrame.
         inplace : bool, default False
             Whether to modify the DataFrame rather than creating a new one.
         verify_integrity : bool, default False
@@ -5957,6 +5955,25 @@ def set_index(
         2 4       4  2014    40
         3 9       7  2013    84
         4 16     10  2014    31
+
+        Append a column to the existing index:
+
+        >>> df.set_index("month", inplace=True)
+        >>> df.set_index("year", append=True)
+                      sale
+        month  year
+        1      2012    55
+        4      2014    40
+        7      2013    84
+        10     2014    31
+
+        >>> df.set_index("year", append=False)
+               sale
+        year
+        2012    55
+        2014    40
+        2013    84
+        2014    31
         """
         inplace = validate_bool_kwarg(inplace, "inplace")
         self._check_inplace_and_allows_duplicate_labels(inplace)

From d053e6cea37c93ecafbab27f646b32d13df44fdc Mon Sep 17 00:00:00 2001
From: SaraInCode <42293506+SaraInCode@users.noreply.github.com>
Date: Sun, 2 Mar 2025 19:42:39 +0100
Subject: [PATCH 3/4] Updated set_index example for append

---
 pandas/core/frame.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/pandas/core/frame.py b/pandas/core/frame.py
index b9e28395d9092..5cf924cfa6c81 100644
--- a/pandas/core/frame.py
+++ b/pandas/core/frame.py
@@ -5958,8 +5958,8 @@ def set_index(
 
         Append a column to the existing index:
 
-        >>> df.set_index("month", inplace=True)
-        >>> df.set_index("year", append=True)
+        >>> a = df.set_index("month")
+        >>> a.set_index("year", append=True)
                       sale
         month  year
         1      2012    55
@@ -5967,7 +5967,7 @@ def set_index(
         7      2013    84
         10     2014    31
 
-        >>> df.set_index("year", append=False)
+        >>> a.set_index("year", append=False)
                sale
         year
         2012    55

From ff0a8055370093afc82ca58603968bb460e10011 Mon Sep 17 00:00:00 2001
From: SaraInCode <42293506+SaraInCode@users.noreply.github.com>
Date: Tue, 4 Mar 2025 19:14:36 +0100
Subject: [PATCH 4/4] Updated set_index example

---
 pandas/core/frame.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/pandas/core/frame.py b/pandas/core/frame.py
index 5cf924cfa6c81..28485bf5fdfd8 100644
--- a/pandas/core/frame.py
+++ b/pandas/core/frame.py
@@ -5958,8 +5958,8 @@ def set_index(
 
         Append a column to the existing index:
 
-        >>> a = df.set_index("month")
-        >>> a.set_index("year", append=True)
+        >>> df = df.set_index("month")
+        >>> df.set_index("year", append=True)
                       sale
         month  year
         1      2012    55
@@ -5967,7 +5967,7 @@ def set_index(
         7      2013    84
         10     2014    31
 
-        >>> a.set_index("year", append=False)
+        >>> df.set_index("year", append=False)
                sale
         year
         2012    55