Extract column value based on another column in Pandas

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Chapters
00:00 Question
00:33 Accepted answer (Score 360)
00:56 Answer 2 (Score 77)
01:09 Answer 3 (Score 53)
01:25 Answer 4 (Score 22)
01:42 Thank you

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Full question
https://stackoverflow.com/questions/3668...

Accepted answer links:
[loc]: http://pandas.pydata.org/pandas-docs/sta...
[iloc]: http://pandas.pydata.org/pandas-docs/sta...

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Content licensed under CC BY-SA
https://meta.stackexchange.com/help/lice...

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Tags
#python #pandas #dataframe

#avk47

ACCEPTED ANSWER

Score 388

You could use loc to get series which satisfying your condition and then iloc to get first element:

In [2]: df
Out[2]:
    A  B
0  p1  1
1  p1  2
2  p3  3
3  p2  4

In [3]: df.loc[df['B'] == 3, 'A']
Out[3]:
2    p3
Name: A, dtype: object

In [4]: df.loc[df['B'] == 3, 'A'].iloc[0]
Out[4]: 'p3'

ANSWER 2

Score 91

You can try query, which is less typing:

df.query('B==3')['A']

ANSWER 3

Score 67

Try:

df[df['B']==3]['A'].item()

assuming df is your pandas.DataFrame.

ANSWER 4

Score 23

Use df[df['B']==3]['A'].values[0] if you just want item itself without the brackets