DOC GH22897 Fix docstring of join in pandas/core/frame.py

Author: JustinZhengBC

pandas/core/frame.py

@@ -6440,6 +6440,8 @@ def append(self, other, ignore_index=False,
     def join(self, other, on=None, how='left', lsuffix='', rsuffix='',
              sort=False):
         """
+        Append columns of another DataFrame.
+
         Join columns with other DataFrame either on index or on a key
         column. Efficiently Join multiple DataFrame objects by index at once by
         passing a list.
@@ -6449,31 +6451,31 @@ def join(self, other, on=None, how='left', lsuffix='', rsuffix='',
         other : DataFrame, Series with name field set, or list of DataFrame
             Index should be similar to one of the columns in this one. If a
             Series is passed, its name attribute must be set, and that will be
-            used as the column name in the resulting joined DataFrame
+            used as the column name in the resulting joined DataFrame.
         on : name, tuple/list of names, or array-like
             Column or index level name(s) in the caller to join on the index
             in `other`, otherwise joins index-on-index. If multiple
             values given, the `other` DataFrame must have a MultiIndex. Can
             pass an array as the join key if it is not already contained in
-            the calling DataFrame. Like an Excel VLOOKUP operation
+            the calling DataFrame. Like an Excel VLOOKUP operation.
         how : {'left', 'right', 'outer', 'inner'}, default: 'left'
             How to handle the operation of the two objects.
 
             * left: use calling frame's index (or column if on is specified)
-            * right: use other frame's index
+            * right: use other frame's index.
             * outer: form union of calling frame's index (or column if on is
-              specified) with other frame's index, and sort it
-              lexicographically
+              specified) with other frame's index, and sort it.
+              lexicographically.
             * inner: form intersection of calling frame's index (or column if
               on is specified) with other frame's index, preserving the order
-              of the calling's one
+              of the calling's one.
         lsuffix : string
-            Suffix to use from left frame's overlapping columns
+            Suffix to use from left frame's overlapping columns.
         rsuffix : string
-            Suffix to use from right frame's overlapping columns
+            Suffix to use from right frame's overlapping columns.
         sort : boolean, default False
             Order result DataFrame lexicographically by the join key. If False,
-            the order of the join key depends on the join type (how keyword)
+            the order of the join key depends on the join type (how keyword).
 
         Notes
         -----
@@ -6485,70 +6487,67 @@ def join(self, other, on=None, how='left', lsuffix='', rsuffix='',
 
         Examples
         --------
+        >>> import pandas as pd
+
         >>> caller = pd.DataFrame({'key': ['K0', 'K1', 'K2', 'K3', 'K4', 'K5'],
         ...                        'A': ['A0', 'A1', 'A2', 'A3', 'A4', 'A5']})
 
         >>> caller
-            A key
-        0  A0  K0
-        1  A1  K1
-        2  A2  K2
-        3  A3  K3
-        4  A4  K4
-        5  A5  K5
+          key   A
+        0  K0  A0
+        1  K1  A1
+        2  K2  A2
+        3  K3  A3
+        4  K4  A4
+        5  K5  A5
 
         >>> other = pd.DataFrame({'key': ['K0', 'K1', 'K2'],
         ...                       'B': ['B0', 'B1', 'B2']})
 
         >>> other
-            B key
-        0  B0  K0
-        1  B1  K1
-        2  B2  K2
+          key   B
+        0  K0  B0
+        1  K1  B1
+        2  K2  B2
 
         Join DataFrames using their indexes.
 
         >>> caller.join(other, lsuffix='_caller', rsuffix='_other')
-
-        >>>     A key_caller    B key_other
-            0  A0         K0   B0        K0
-            1  A1         K1   B1        K1
-            2  A2         K2   B2        K2
-            3  A3         K3  NaN       NaN
-            4  A4         K4  NaN       NaN
-            5  A5         K5  NaN       NaN
-
+          key_caller   A key_other    B
+        0         K0  A0        K0   B0
+        1         K1  A1        K1   B1
+        2         K2  A2        K2   B2
+        3         K3  A3       NaN  NaN
+        4         K4  A4       NaN  NaN
+        5         K5  A5       NaN  NaN
 
         If we want to join using the key columns, we need to set key to be
         the index in both caller and other. The joined DataFrame will have
         key as its index.
 
         >>> caller.set_index('key').join(other.set_index('key'))
-
-        >>>      A    B
-            key
-            K0   A0   B0
-            K1   A1   B1
-            K2   A2   B2
-            K3   A3  NaN
-            K4   A4  NaN
-            K5   A5  NaN
+              A    B
+        key
+        K0   A0   B0
+        K1   A1   B1
+        K2   A2   B2
+        K3   A3  NaN
+        K4   A4  NaN
+        K5   A5  NaN
 
         Another option to join using the key columns is to use the on
         parameter. DataFrame.join always uses other's index but we can use any
         column in the caller. This method preserves the original caller's
         index in the result.
 
         >>> caller.join(other.set_index('key'), on='key')
-
-        >>>     A key    B
-            0  A0  K0   B0
-            1  A1  K1   B1
-            2  A2  K2   B2
-            3  A3  K3  NaN
-            4  A4  K4  NaN
-            5  A5  K5  NaN
-
+          key   A    B
+        0  K0  A0   B0
+        1  K1  A1   B1
+        2  K2  A2   B2
+        3  K3  A3  NaN
+        4  K4  A4  NaN
+        5  K5  A5  NaN
 
         See also
         --------