diff --git a/pandas/core/groupby/groupby.py b/pandas/core/groupby/groupby.py index 5f462de19a398..c5609672a9e5a 100644 --- a/pandas/core/groupby/groupby.py +++ b/pandas/core/groupby/groupby.py @@ -2637,7 +2637,7 @@ def cumcount(self, ascending: bool = True): @final @Substitution(name="groupby") - @Appender(_common_see_also) + @Substitution(see_also=_common_see_also) def rank( self, method: str = "average", @@ -2671,6 +2671,41 @@ def rank( Returns ------- DataFrame with ranking of values within each group + %(see_also)s + Examples + -------- + >>> df = pd.DataFrame( + ... { + ... "group": ["a", "a", "a", "a", "a", "b", "b", "b", "b", "b"], + ... "value": [2, 4, 2, 3, 5, 1, 2, 4, 1, 5], + ... } + ... ) + >>> df + group value + 0 a 2 + 1 a 4 + 2 a 2 + 3 a 3 + 4 a 5 + 5 b 1 + 6 b 2 + 7 b 4 + 8 b 1 + 9 b 5 + >>> for method in ['average', 'min', 'max', 'dense', 'first']: + ... df[f'{method}_rank'] = df.groupby('group')['value'].rank(method) + >>> df + group value average_rank min_rank max_rank dense_rank first_rank + 0 a 2 1.5 1.0 2.0 1.0 1.0 + 1 a 4 4.0 4.0 4.0 3.0 4.0 + 2 a 2 1.5 1.0 2.0 1.0 2.0 + 3 a 3 3.0 3.0 3.0 2.0 3.0 + 4 a 5 5.0 5.0 5.0 4.0 5.0 + 5 b 1 1.5 1.0 2.0 1.0 1.0 + 6 b 2 3.0 3.0 3.0 2.0 3.0 + 7 b 4 4.0 4.0 4.0 3.0 4.0 + 8 b 1 1.5 1.0 2.0 1.0 2.0 + 9 b 5 5.0 5.0 5.0 4.0 5.0 """ if na_option not in {"keep", "top", "bottom"}: msg = "na_option must be one of 'keep', 'top', or 'bottom'"