get new list from pivot_table?

时间:2019-03-17 22:37:02

标签: python-3.x pandas pivot-table

I'm using python 3 and pandas. I have this pivot table below.

    >>> print(p.head())
    question_id               1       2                       3                          4        ...                       26              27              28              29
    assessment_attempt_id
                                                                         ...                                                                         
243908                 21-24  Female  4th year undergraduate                      White       ...                 Disagree        Disagree           Agree           Agree
290934                 25-29    Male    Prefer Not to Answer  Black or African American       ...                  Neutral         Neutral         Neutral         Neutral
312457                 18-20  Female  1st year undergraduate                      White       ...           Strongly Agree  Strongly Agree  Strongly Agree  Strongly Agree
312766                 18-20  Female  2nd year undergraduate       Hispanic or Latina/o       ...                    Agree           Agree           Agree           Agree
312786                 21-24  Female  4th year undergraduate  Black or African American       ...        Strongly Disagree           Agree           Agree           Agree

It is produced from this command:

    p= pandas.pivot_table(df, index=["assessment_attempt_id"], columns=["question_id"], values="text", aggfunc='first')

The table is basically exactly what I want. Now I just want columns 1,2,3,4 and the assessment_attempt_id column in a Datatable, so I can join that data by assessment_attempt_id with another existing data table.

Normally I would subset the data by doing something like this:

    df1 = df[['a','b']]

but that produces and error: KeyError: "['1' '2'] not in index" It seems like this should be a simple and solved problem but I can not find the answer. I also tried a groupby variation which produced the same output, and also I could not extract the columns I wanted. I assume I can't at the multi-index, but I don't know how. Thank you.

0 个答案:

没有答案