使用方法链接将数据帧复制到新变量

Question

是否可以将方法链中间的数据帧复制到新变量？ 比如：

import pandas as pd

df = pd.DataFrame([[2,4,6],
                  [8,10,12],
                  [14,16,18],
                  ])

df = (df.assign(new_var=100)
      .div(2)
      .copy_to_new_variable(df_imag)  # Imaginated method to copy df to df_new.
      .div(10)
      )

print(df_imag)

然后会返回：

|   | 0   | 1   | 2   | new_var |
| - | --- | --- | --- | ------- |
| 0 | 1.0 | 2.0 | 3.0 | 50.0    |
| 1 | 4.0 | 5.0 | 6.0 | 50.0    |
| 2 | 7.0 | 8.0 | 9.0 | 50.0    |

Answer 1

使用

:=

运算符：

df = (df_imag := df.assign(new_var=100).div(2)).div(10)
print(df)
print(df_imag)

打印：

     0    1    2  new_var
0  0.1  0.2  0.3      5.0
1  0.4  0.5  0.6      5.0
2  0.7  0.8  0.9      5.0

     0    1    2  new_var
0  1.0  2.0  3.0     50.0
1  4.0  5.0  6.0     50.0
2  7.0  8.0  9.0     50.0