为什么熊猫列没有转换为 Int64？

Question

这是我的代码：import pandas as pdimport numpy as npdata = {'ID': [1,2,3,4,5,6,7,8,9],       'Doc':['Order','Order','Inv','Order','Order','Shp','Order', 'Order','Inv'],       'Rep':[101,101,101,102,102,102,103,103,103]}df = pd.DataFrame(data)#df['concat']= (df['ID'].convert_dtypes(convert_string = True) + "1").convert_dtypes(convert_integer = True)df['concat']= (df['ID'].astype(str) + "1").convert_dtypes(convert_integer = True)print(df['concat'].dtype)输出：string为什么不是以及如何获得它？df['concat']Int64

Answer 1

尝试

>>> df['concat'] = df['ID'].astype(str).add('1').astype('int64')

0    11

1    21

2    31

3    41

4    51

5    61

6    71

7    81

8    91

Name: ID, dtype: int64