I have a column (dataframe) that has numerical values like the ones shown below:

I have the next lists:

asia = [22, 23, 0, 1, 2, 3, 4, 5, 6, 7]    
asia_europe = [8]    
europe = [9, 10, 11, 12]    
europe_america = [13, 14, 15, 16]    
america = [17, 18, 19, 20, 21]

I want the numbers in the column to be replaced with their respective text that comes from the lists so that my dataframe looks like this:

I don't know if there is a way to do this using pandas or if I have to use a for loop.

CodePudding user response：

You need to build a dictionary to reference the region from the number. For that a dictionary comprehension is handy:

d = dict(asia = [22, 23, 0, 1, 2, 3, 4, 5, 6, 7],
         asia_europe = [8],
         europe = [9, 10, 11, 12],
         europe_america = [13, 14, 15, 16],
         america = [17, 18, 19, 20, 21])

d2 = {v:k for k,l in d.items() for v in l}
# {0: 'asia',
#  1: 'asia',
#   ...
# 21: 'america'}

Then map the value to the regions:

df['New Column'] = df['Old Column'].map(d2)