From 18c24e231d0e2a82f40451025469c6873f596080 Mon Sep 17 00:00:00 2001
From: Paul Ganssle <paul@ganssle.io>
Date: Wed, 7 Oct 2020 13:15:22 -0400
Subject: [PATCH 1/3] REGR: Allow positional arguments in DataFrame.agg

Although `DataFrame.agg` is documented as accepting `func, axis, *args, **kwargs`
with `*args` and `**kwargs` passed to `func`, passing positional
arguments raises a TypeError.

The reason for this is that the internal call to `self._aggregate` uses
a keyword argument (axis) before passing *args and `**kwargs`, and as such the
first positional argument is always interpreted as a second
specification of `axis`, which raises TypeError.

Prior to commit 433c9007781080658553fbef1a4d0c2813b404c0, TypeErrors
were being suppressed, falling back to `self.apply`, which in v1.1.0
turned into an error.

This fixes issue GH-36948.
---
 pandas/core/frame.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/core/frame.py b/pandas/core/frame.py
index 29c63b030cdd5..87724078ff163 100644
--- a/pandas/core/frame.py
+++ b/pandas/core/frame.py
@@ -7406,7 +7406,7 @@ def aggregate(self, func=None, axis=0, *args, **kwargs):
 
         result = None
         try:
-            result, how = self._aggregate(func, axis=axis, *args, **kwargs)
+            result, how = self._aggregate(func, axis, *args, **kwargs)
         except TypeError as err:
             exc = TypeError(
                 "DataFrame constructor called with "

From 1fd760501ee84eab48aaf439566884960f0747c0 Mon Sep 17 00:00:00 2001
From: Paul Ganssle <paul@ganssle.io>
Date: Wed, 7 Oct 2020 13:50:00 -0400
Subject: [PATCH 2/3] Add test for DataFrame.agg with *args, **kwargs

---
 pandas/tests/frame/apply/test_frame_apply.py | 28 ++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/pandas/tests/frame/apply/test_frame_apply.py b/pandas/tests/frame/apply/test_frame_apply.py
index 5c6a47c57970b..598da9c52731e 100644
--- a/pandas/tests/frame/apply/test_frame_apply.py
+++ b/pandas/tests/frame/apply/test_frame_apply.py
@@ -1463,6 +1463,34 @@ def test_agg_cython_table_raises(self, df, func, expected, axis):
         with pytest.raises(expected, match=msg):
             df.agg(func, axis=axis)
 
+    @pytest.mark.parametrize("axis", [0, 1])
+    @pytest.mark.parametrize(
+        "args, kwargs",
+        [
+            ((1, 2, 3), {}),
+            ((8, 7, 15), {}),
+            ((1, 2), {}),
+            ((1,), {"b": 2}),
+            ((), {"a": 1, "b": 2}),
+            ((), {"a": 2, "b": 1}),
+            ((), {"a": 1, "b": 2, "c": 3}),
+        ],
+    )
+    def test_agg_args_kwargs(self, axis, args, kwargs):
+        def f(x, a, b, c=3):
+            return x.sum() + (a + b) / c
+
+        df = pd.DataFrame([[1, 2], [3, 4]])
+
+        if axis == 0:
+            expected = pd.Series([5.0, 7.0])
+        else:
+            expected = pd.Series([4.0, 8.0])
+
+        result = df.agg(f, axis, *args, **kwargs)
+
+        tm.assert_series_equal(result, expected)
+
     @pytest.mark.parametrize("num_cols", [2, 3, 5])
     def test_frequency_is_original(self, num_cols):
         # GH 22150

From 4a37cd348f5692734b21d4d6dad59c184c989fdd Mon Sep 17 00:00:00 2001
From: Paul Ganssle <paul@ganssle.io>
Date: Thu, 8 Oct 2020 10:55:17 -0400
Subject: [PATCH 3/3] What's new entry

---
 doc/source/whatsnew/v1.1.4.rst | 1 +
 1 file changed, 1 insertion(+)

diff --git a/doc/source/whatsnew/v1.1.4.rst b/doc/source/whatsnew/v1.1.4.rst
index d0d03021629c6..b85a85a7e0595 100644
--- a/doc/source/whatsnew/v1.1.4.rst
+++ b/doc/source/whatsnew/v1.1.4.rst
@@ -15,6 +15,7 @@ including other versions of pandas.
 Fixed regressions
 ~~~~~~~~~~~~~~~~~
 - Fixed regression where attempting to mutate a :class:`DateOffset` object would no longer raise an ``AttributeError`` (:issue:`36940`)
+- Fixed regression where :meth:`DataFrame.agg` would fail with :exc:`TypeError` when passed positional arguments to be passed on to the aggregation function (:issue:`36948`).
 
 .. ---------------------------------------------------------------------------