pandas 如何在单个数据框中合并具有相同索引的行？
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How to merge rows with same index on a single data frame?
提问by ChiefsCreation
I have a dataframe that looks like this:
我有一个看起来像这样的数据框：
A B C
1 1234 Win
1 2345 Win
2 1987 Loss
3 3456 Win
3 4567 Win
And I want this to become:
我希望这变成：
A B C
1 1234,2345 Win
2 1987 Loss
3 3456,4567 Win
Note: C values always have the same value for the same index.
注意：对于相同的索引，C 值始终具有相同的值。
Anyone can help? Thanks!
任何人都可以帮忙吗？谢谢！
回答by EdChum
You can groupbyon 'A' and 'C' seeing as their relationship is the same, cast the 'B' column to str and joinwith a comma:
您可以groupby在 'A' 和 'C' 上看到它们的关系是相同的，将 'B' 列转换为 str 并join使用逗号：
In [23]:
df.groupby(['A','C'])['B'].apply(lambda x: ','.join(x.astype(str))).reset_index()
Out[23]:
A C B
0 1 Win 1234,2345
1 2 Loss 1987
2 3 Win 3456,4567
