import pandas as pd
import rpy2.robjects as ro
from rpy2.robjects.packages import importr
from rpy2.robjects import pandas2ri
from rpy2.robjects.conversion import localconverter
pd_df = pd.DataFrame({'int_values': [1,2,3],'str_values': ['abc', 'def', 'ghi']})
print(pd_df)
       int_values str_values
    0           1        abc
    1           2        def
    2           3        ghi
with localconverter(ro.default_converter + pandas2ri.converter):
    r_from_pd_df = ro.conversion.py2rpy(pd_df)
print(r_from_pd_df)
       int_values str_values
    0           1        abc
    1           2        def
    2           3        ghi

# 1. The conversion is automatically happening when calling R functions. For example, when calling the R function , base::summary
base = importr('base')
with localconverter(ro.default_converter + pandas2ri.converter):
      df_summary = base.summary(pd_df)   #自动转换
print(df_summary) # ['Min.   :1.0  ' '1st Qu.:1.5  ' 'Median :2.0  ' 'Mean   :2.0  '
     '3rd Qu.:2.5  ' 'Max.   :3.0  ' 'Length:3          ' 'Class :character  '
     'Mode  :character  ' NA_character_ NA_character_ NA_character_]

# 2. Note that a ContextManager is used to limit the scope of the conversion. Without it, rpy2 will not know how to convert a pandas data frame:
try:
    df_summary = base.summary(pd_df)
except NotImplementedError as nie:
    print('NotImplementedError:')
    print(nie)