Recoding Categorical to Numerical

[Peter Otten]

On 14/08/2021 00:33, John Griner wrote:
> Hello, and thanks in advance,
> 
>       I am trying to recode categorical variable to numeric.  Despite using
> lambda, If else, dummy-recoding, and so forth, what I get is from ONE
> column that has 4 variables (City, Town, Suburb, Rural), I get FOUR columns:
> 
> 
> 
> localeDummy_City          localeDummy_Town      localeDummy_Suburb
> localeDummy_Rural       locale_recode
> 
> 
> 
> with the corresponding numeric variable.
> 
> 
> 
> What I want is the recode to have ONE column that has the numeric
> conversion.
> 
> 
> 
> For instance:
> 
> 
> local_recode
> 
> 2
> 
> 4
> 
> 4
> 
> 6
> 
> 2
> 
> 8
> 
> 6
> 
> 2
> 
> 8
> 
> 2
> 
> 2
> 
> 4
> 
> 6
> 
> 4
> 
> 8
> 
> and so forth, where I have set City to 2, and Town to 4, etc.
> 
> 
> Again, thanks, John

My crystal ball says you want

import pandas

df = pandas.DataFrame(
     [
         [("City", "Suburb")],
         [("Town", "City", "Suburb")],
         [("Rural",)]
     ],
     columns=["before"]
)

flags = dict(
     City=1,
     Town=2,
     Suburb=4,
     Rural=8
)

df["after"] = df["before"].apply(
     lambda names: sum(flags[name] for name in set(names))
)

print(df)

If that's not it show us your failing code, preferably as a small 
self-contained script that also generates the required input data. Use 
cut and paste, and include it into the message body as attachments are 
usually removed.