From ed5c2c297f27c28c3aa4066248f9e93c989b81a8 Mon Sep 17 00:00:00 2001
From: Daniel Saxton <>
Date: Fri, 6 Sep 2019 16:51:46 -0500
Subject: [PATCH 1/3] Clean error message

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

diff --git a/pandas/core/groupby/ops.py b/pandas/core/groupby/ops.py
index bcda25bf3ce39..d5d1c50f34c6f 100644
--- a/pandas/core/groupby/ops.py
+++ b/pandas/core/groupby/ops.py
@@ -464,7 +464,7 @@ def _cython_operation(self, kind, values, how, axis, min_count=-1, **kwargs):
         # are not setup for dim transforming
         if is_categorical_dtype(values) or is_sparse(values):
             raise NotImplementedError(
-                "{} are not support in cython ops".format(values.dtype)
+                "{} are not supported in Cython operations".format(values.dtype)
             )
         elif is_datetime64_any_dtype(values):
             if how in ["add", "prod", "cumsum", "cumprod"]:

From d81d90b664b97eb89b8f857d1afd25028e379c31 Mon Sep 17 00:00:00 2001
From: Daniel Saxton <>
Date: Fri, 6 Sep 2019 20:56:35 -0500
Subject: [PATCH 2/3] Edit message

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

diff --git a/pandas/core/groupby/ops.py b/pandas/core/groupby/ops.py
index d5d1c50f34c6f..02d5586f2288b 100644
--- a/pandas/core/groupby/ops.py
+++ b/pandas/core/groupby/ops.py
@@ -464,7 +464,7 @@ def _cython_operation(self, kind, values, how, axis, min_count=-1, **kwargs):
         # are not setup for dim transforming
         if is_categorical_dtype(values) or is_sparse(values):
             raise NotImplementedError(
-                "{} are not supported in Cython operations".format(values.dtype)
+                "{} dtype not supported".format(values.dtype)
             )
         elif is_datetime64_any_dtype(values):
             if how in ["add", "prod", "cumsum", "cumprod"]:

From c43ae34f93ba9b1b20d2f87ebc1e2cf386a8b87a Mon Sep 17 00:00:00 2001
From: Daniel Saxton <>
Date: Sat, 7 Sep 2019 09:06:00 -0500
Subject: [PATCH 3/3] Format

---
 pandas/core/groupby/ops.py | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/pandas/core/groupby/ops.py b/pandas/core/groupby/ops.py
index 02d5586f2288b..1a3f0da3cf92b 100644
--- a/pandas/core/groupby/ops.py
+++ b/pandas/core/groupby/ops.py
@@ -463,9 +463,7 @@ def _cython_operation(self, kind, values, how, axis, min_count=-1, **kwargs):
         # categoricals are only 1d, so we
         # are not setup for dim transforming
         if is_categorical_dtype(values) or is_sparse(values):
-            raise NotImplementedError(
-                "{} dtype not supported".format(values.dtype)
-            )
+            raise NotImplementedError("{} dtype not supported".format(values.dtype))
         elif is_datetime64_any_dtype(values):
             if how in ["add", "prod", "cumsum", "cumprod"]:
                 raise NotImplementedError(