pandas df.ix [number，column]访问与df [column] .ix [number]不同的标量类型

For example,

import pandas as pd
import numpy as np

df1 = pd.DataFrame({'frames':np.arange(3), 'r':np.repeat(3, 3), \
'x':np.random.rand(3), 'y':list('041')}, index=list('abc'))

  frames  r       x   y
a      0  3  0.1241  '0'
b      1  3  0.4109  '4'
c      2  3  0.8714  '1'
import pandas as pd
import numpy