列名稱在熊貓中的異常排序

Question

當我將數據框從熊貓導出到Excel電子表格時，我的列順序如下所示，其中“ 10個最大事件”被認為是“ 1個最大事件”之后的第二個，而不是“ 2個最大事件”。 我希望它以數字順序顯示。 即“ 1個最大事件”，“ 2個最大事件”，“ 10個最大事件”

ID_1    Permit No.        ID_2       1 Largest Event    10 Largest Event    2 Largest Event
10220   To Be Permitted 0010001-24.1       4.0548                  0.822    3.9611

為什么會這樣呢？ 這是一個較小的格式化錯誤，但可能會讓人感到非常討厭。

Answer 1

從natsort reindex

from natsort import natsorted
l=['1 Largest Event','10 Largest Event','2 Largest Event']
natsorted(l)
Out[789]: ['1 Largest Event', '2 Largest Event', '10 Largest Event']
df=df.reindex(columns=natsorted(list(df)))

Answer 2

問題是您的列按字典順序像字符串一樣排序。

因此需要使用自定義函數進行排序，方法是先將拆分值轉換為int ：

df = df[sorted(df.columns, key=lambda x: int(x.split()[0]))]

樣品 ：

cols = ['1 Largest Event', 
        '10 Largest Event', 
        '2 Largest Event',
        '3 Largest Event',
        '4 Largest Event',
        '5 Largest Event', 
        '6 Largest Event', 
        '7 Largest Event', 
        '8 Largest Event', 
        '9 Largest Event']

df = pd.DataFrame(0, columns=cols, index=[0])
print (df)
   1 Largest Event  10 Largest Event  2 Largest Event  3 Largest Event  \
0                0                 0                0                0   

   4 Largest Event  5 Largest Event  6 Largest Event  7 Largest Event  \
0                0                0                0                0   

   8 Largest Event  9 Largest Event  

df = df[sorted(df.columns, key=lambda x: int(x.split()[0]))]
print (df)

   1 Largest Event  2 Largest Event  3 Largest Event  4 Largest Event  \
0                0                0                0                0   

   5 Largest Event  6 Largest Event  7 Largest Event  8 Largest Event  \
0                0                0                0                0   

   9 Largest Event  10 Largest Event  
0                0                 0  

編輯：

您還可以過濾最后3列進行排序：

df = df[df.columns[:3].tolist() + sorted(df.columns[3:], key=lambda x: int(x.split()[0]))]
print (df)
    ID_1       Permit No.          ID_2  1 Largest Event  2 Largest Event  \
0  10220  To Be Permitted  0010001-24.1           4.0548           3.9611   

   10 Largest Event  
0             0.822