PyPackage01---Pandas11_explode方法使用

Intro

hive中有explode方法，進行單行轉多行的操作。pandas也有類似的功能，versionadded:: 0.25.0。直接看個case。

Signature: df1.explode(column: Union[str, Tuple], ignore_index: bool = False) -> 'DataFrame'

Docstring:

Transform each element of a list-like to a row, replicating index values.



.. versionadded:: 0.25.0



Parameters

----------

column : str or tuple

 Column to explode.

ignore_index : bool, default False

 If True, the resulting index will be labeled 0, 1, …, n - 1.



 .. versionadded:: 1.1.0



Returns

-------

DataFrame

 Exploded lists to rows of the subset columns;

 index will be duplicated for these rows.



Raises

------

ValueError :

 if columns of the frame are not unique.



See Also

--------

DataFrame.unstack : Pivot a level of the (necessarily hierarchical)

 index labels.

DataFrame.melt : Unpivot a DataFrame from wide format to long format.

Series.explode : Explode a DataFrame from list-like columns to long format.



Notes

-----

This routine will explode list-likes including lists, tuples,

Series, and np.ndarray. The result dtype of the subset rows will

be object. Scalars will be returned unchanged. Empty list-likes will

result in a np.nan for that row.




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Case

import
pandas
as


1.

pd.
__version__


1.

'1.1.5'


1.

id
= [
'a',
'b',
'c']


id2
= [
4,
6,[
2,
3,
8]]


id3
= [
1,
1,
1]


df
=
pd.
DataFrame({
'id':
id,
'id2':
id2,
'id3':
id3})


1.
2.
3.
4.

id

id2

id3

0

a

4

1

1

b

6

1

2

c

[2, 3, 8]

1

df.
explode(
'id2')


1.

id

id2

id3

0

a

4

1

1

b

6

1

2

c

2

1

2

c

3

1

2

c

8

1

2021-03-25 於南京市江寧區九龍湖