Remap values in pandas column with a dict

Question

I have a dictionary which looks like this: di = {1: \"A\", 2: \"B\"}

I would like to apply it to the \"col1\" column of a dataframe similar to:

Answer 1

DSM has the accepted answer, but the coding doesn't seem to work for everyone. Here is one that works with the current version of pandas (0.23.4 as of 8/2018):

import pandas as pd

df = pd.DataFrame({'col1': [1, 2, 2, 3, 1],
            'col2': ['negative', 'positive', 'neutral', 'neutral', 'positive']})

conversion_dict = {'negative': -1, 'neutral': 0, 'positive': 1}
df['converted_column'] = df['col2'].replace(conversion_dict)

print(df.head())

You'll see it looks like:

   col1      col2  converted_column
0     1  negative                -1
1     2  positive                 1
2     2   neutral                 0
3     3   neutral                 0
4     1  positive                 1

The docs for pandas.DataFrame.replace are here.