pandas融化功能

pandas融化功能

melt

带您到那里。

In [29]: m = pd.melt(df, id_vars=['Year'], var_name='Name')

除了一切都有

Group

。为了做到这一点，我们还需要重塑

d

一点。

In [30]: d2 = {}In [31]: for k, v in d.items():    for item in v:        d2[item] = k   ....:In [32]: d2Out[32]: {'Amy': 'A', 'Ben': 'B', 'Bob': 'B', 'Carl': 'C', 'Chris': 'C'}In [34]: m['Group'] = m['Name'].map(d2)In [35]: mOut[35]:    Year   Name  value Group0   2013    Amy      2     A1   2014    Amy      9     A2   2013    Bob      4     B3   2014    Bob      2     B4   2013   Carl      7     C..   ...    ...    ...   ...7   2014  Chris      5     C8   2013    Ben      1     B9   2014    Ben      5     B10  2013  Other      3   NaN11  2014  Other      6   NaN[12 rows x 4 columns]

并将“其他”从

Name

转移到

Group

In [8]: mask = m['Name'] == 'Other'In [9]: m.loc[mask, 'Name'] = ''In [10]: m.loc[mask, 'Group'] = 'Other'In [11]: mOut[11]:    Year   Name  value  Group0   2013    Amy      2      A1   2014    Amy      9      A2   2013    Bob      4      B3   2014    Bob      2      B4   2013   Carl      7      C..   ...    ...    ...    ...7   2014  Chris      5      C8   2013    Ben      1      B9   2014    Ben      5      B10  2013  3  Other11  2014  6  Other[12 rows x 4 columns]