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pythonpandasdataframeunique

Pandas dataframe get unique value of a column

I'm trying to get the unique available value for each site. The original pandas dataframe is with three columns:

Site Available Capacity
A 7 20
A 7 20
A 8 20
B 15 35
B 15 35
C 12 25
C 12 25
C 11 25

and I want to get the unique available of each site. The desired table is like below:

Site Unique Available
A 7
8
B 15
C 12
11
Solution

  • You can get the lists of unique available per site with GroupBy.unique()

    >>> df.groupby('Site')['Available'].unique()
Site
A      [7, 8]
B        [15]
C    [12, 11]
Name: Available, dtype: object

    Then with explode() you can expand these lists and with reset_index() get the index back to a column:

    >>> df.groupby('Site')['Available'].unique().explode().reset_index()
  Site Available
0    A         7
1    A         8
2    B        15
3    C        12
4    C        11

    Otherwise simply get both columns and remove duplicates:

    >>> df[['Site', 'Available']].drop_duplicates()
  Site  Available
0    A          7
2    A          8
3    B         15
5    C         12
7    C         11