pyspark.pandas.groupby.GroupBy.backfill¶
-
GroupBy.backfill(limit: Optional[int] = None) → FrameLike¶ Synonym for DataFrame.fillna() with
method=`bfill`.- Parameters
- axis{0 or index}
1 and columns are not supported.
- inplaceboolean, default False
Fill in place (do not create a new object)
- limitint, default None
If method is specified, this is the maximum number of consecutive NaN values to forward/backward fill. In other words, if there is a gap with more than this number of consecutive NaNs, it will only be partially filled. If method is not specified, this is the maximum number of entries along the entire axis where NaNs will be filled. Must be greater than 0 if not None
- Returns
- DataFrame
DataFrame with NA entries filled.
Examples
>>> df = ps.DataFrame({ ... 'A': [1, 1, 2, 2], ... 'B': [2, 4, None, 3], ... 'C': [None, None, None, 1], ... 'D': [0, 1, 5, 4] ... }, ... columns=['A', 'B', 'C', 'D']) >>> df A B C D 0 1 2.0 NaN 0 1 1 4.0 NaN 1 2 2 NaN NaN 5 3 2 3.0 1.0 4
Propagate non-null values backward.
>>> df.groupby(['A']).bfill().sort_index() B C D 0 2.0 NaN 0 1 4.0 NaN 1 2 3.0 1.0 5 3 3.0 1.0 4