Pandas 循环遍历数据框列表和更改索引
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Pandas Loop through list of Data Frames and Change Index
提问by geeb.24
This is a basic quesion, but I want to loop through a list of data frames and for each data frame, set the index as one of the columns in the data frame. The issue with the code below is that it doesn't save the data frame with a new index. How do I format this For loop so that the dataframes are permanently changed outside of the for loop? Thanks.
这是一个基本问题，但我想遍历数据框列表，并为每个数据框将索引设置为数据框中的列之一。下面代码的问题在于它没有使用新索引保存数据框。如何格式化此 For 循环，以便在 for 循环之外永久更改数据帧？谢谢。
dflist = [df_1, df_2, df_3]
for i in dflist:
i = i.set_index('column_2')
回答by Oasa
As you have probably guessed, i is just a temporary value. Use i as only an index using enumerate
正如您可能已经猜到的那样， i 只是一个临时值。使用 enumerate 将 i 仅用作索引
for i, df in enumerate(dflist):
dflist[i] = dflist[i].set_index('column_2'))
回答by Love T?tting
for i in dflist:
i.set_index('column_2', inplace=True)
回答by ChuHo
Try it with the in place option:
i = i.set_index('column_2', inplace=True)
尝试使用就地选项：
i = i.set_index('column_2', inplace=True)
