关于python：Pandas – DataFrame reindex函数返回一个警告

Pandas - DataFrame reindex function returns a warning

代码有什么问题？：
它返回一个警告：

Warning (from warnings module): File
"C:\Python27\lib\site-packages
umpy\core
umeric.py", line 2515
return bool(asarray(a1 == a2).all()) FutureWarning: elementwise comparison failed; returning scalar instead, but in the future will
perform elementwise comparison

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import pandas as pd
import numpy as np

Data1 = {'State':['Ohio','Ohio','Ohio','Nevada','Nevada'],'Year':[2000,2001,2002,2001,2002],'POP':[1.5,1.7,3.6,2.4,2.9]}

Frame4 =pd.DataFrame(Data1)
print('
')
print Frame4

Frame5 = Frame4.reindex(['a','b','c','d','e'])
print Frame5

my o/p
POP State Year
0 1.5 Ohio 2000
1 1.7 Ohio 2001
2 3.6 Ohio 2002
3 2.4 Nevada 2001
4 2.9 Nevada 2002

Warning (from warnings module):
File"C:\Python27\lib\site-packages
umpy\core
umeric.py", line 2515
return bool(asarray(a1 == a2).all())
FutureWarning: elementwise comparison failed; returning scalar instead, but in the future will perform elementwise comparison
POP State Year
a NaN NaN NaN
b NaN NaN NaN
c NaN NaN NaN
d NaN NaN NaN
e NaN NaN NaN

试试这个：

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Frame4 =pd.DataFrame(Data1)
print('
')
print Frame4

Frame4.index = ['a','b','c','d','e']
print Frame4

POP State Year
0 1.5 Ohio 2000
1 1.7 Ohio 2001
2 3.6 Ohio 2002
3 2.4 Nevada 2001
4 2.9 Nevada 2002

POP State Year
a 1.5 Ohio 2000
b 1.7 Ohio 2001
c 3.6 Ohio 2002
d 2.4 Nevada 2001
e 2.9 Nevada 2002