From ced66b568a837572daf5bc0a3c5c7b258cc4ba34 Mon Sep 17 00:00:00 2001
From: brandon-b-miller <53796099+brandon-b-miller@users.noreply.github.com>
Date: Wed, 22 Sep 2021 21:34:27 -0500
Subject: [PATCH] Align `DataFrame.apply` signature with pandas (#9275)

Aligns the function signature for `cudf.DataFrame.apply` with that of `pandas.DataFrame.apply`. This is needed so that dask can build on a common `apply` interface between backends among other reasons.

Authors:
  - https://github.com/brandon-b-miller

Approvers:
  - GALI PREM SAGAR (https://github.com/galipremsagar)

URL: https://github.com/rapidsai/cudf/pull/9275
---
 python/cudf/cudf/core/dataframe.py | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/python/cudf/cudf/core/dataframe.py b/python/cudf/cudf/core/dataframe.py
index 1143f85a4e6..901bdfe42c8 100644
--- a/python/cudf/cudf/core/dataframe.py
+++ b/python/cudf/cudf/core/dataframe.py
@@ -4742,7 +4742,9 @@ def query(self, expr, local_dict=None):
             boolmask = queryutils.query_execute(self, expr, callenv)
             return self._apply_boolean_mask(boolmask)
 
-    def apply(self, func, axis=1):
+    def apply(
+        self, func, axis=1, raw=False, result_type=None, args=(), **kwargs
+    ):
         """
         Apply a function along an axis of the DataFrame.
 
@@ -4756,12 +4758,17 @@ def apply(self, func, axis=1):
         ----------
         func : function
             Function to apply to each row.
-
         axis : {0 or 'index', 1 or 'columns'}, default 0
             Axis along which the function is applied:
             * 0 or 'index': apply function to each column.
               Note: axis=0 is not yet supported.
             * 1 or 'columns': apply function to each row.
+        raw: bool, default False
+            Not yet supported
+        result_type: {'expand', 'reduce', 'broadcast', None}, default None
+            Not yet supported
+        args: tuple
+            Not yet supported
 
         Examples
         --------
@@ -4910,6 +4917,12 @@ def apply(self, func, axis=1):
             raise ValueError(
                 "DataFrame.apply currently only supports row wise ops"
             )
+        if raw:
+            raise ValueError("The `raw` kwarg is not yet supported.")
+        if result_type is not None:
+            raise ValueError("The `result_type` kwarg is not yet supported.")
+        if args or kwargs:
+            raise ValueError("args and kwargs are not yet supported.")
 
         return cudf.Series(func(self))