Pandas - how to convert r dataframe back to pandas?

Question

I converted a pandas df to r using the the below:

import pandas as pd import pandas.rpy.common as com import rpy2.robjects as ro from rpy2.robjects.packages import importr rdf = com.convert_to_r_dataframe(df) 

How do I convert rdf back to a pandas df?

df = f(rdf) ? 

Answer 1

Since rpy2 release 2.4.0 converting data frames back and forth between rpy2 and pandas is included as an optional module. With it, no need to convert explicitly, it will be done on the fly.

The documentation contains examples (also available as a Jupyter notebook - link available near the top of the page): https://rpy2.github.io/doc/latest/html/pandas.html#interoperability-with-pandas

Note: The original answer to this question recommended the following.

from rpy2.robjects import pandas2ri pandas2ri.activate() 

If wishing to convert explicitly for any reason, the functions are pandas2ri.py2ri() and pandas2ri.ri2py() (they were pandas2ri.pandas2ri() and pandas2ri.ri2pandas()).

Note: Since rpy2 release 3.3.0 explicit conversion is done as follows

import rpy2.robjects as ro  dt = pd.DataFrame() # To R DataFrame r_dt = ro.conversion.py2rpy(dt) # To pandas DataFrame pd_dt = ro.conversion.rpy2py(r_dt) 

For more details check out this link.

Answer 2

As suggested by lgautier, it can be done with pandas2ri.

Here is sample code for convert rpy dataframe (rdf) to pandas dataframe (pd_df):

from rpy2.robjects import pandas2ri  pd_df = pandas2ri.ri2py_dataframe(rdf)