Python calling a list by name

September 13, 2022

Consider the case where I have three dataframes, that are called df1, df2 and df3.

df1 has 5 columns: x1, x2, x3, age, height.
df2 has 3 columns: x1, x2, weight.
df3 has 4 columns: x1, x2, x3, bmi.

For each of these dataframes, I want to create a list of the demographic variables e.g.

df1_demographics=['age', 'height']
df2_demographics=['weight']
df3_demographics=['bmi']

I want to be able to call the list in a loop in the following way:

for dataset in df1, df2, df3:

   print(dataset_demographics)

My actual loop is very long and I need to loop through the dataframes. That’s why I specifically want a way of calling the lists within a for loop looping through the dataframes.

The desired output of this loop would be

['age', 'height']
['weight']
['bmi']

>Solution :

I’m not entirely sure what your question is asking. Are you looking to associate a subset of columns with each of your dataframes like so?

demographic_cols = [
    ['age', 'height'],
    ['weight'],
    ['bmi']
]
dataframes = [df1, df2, df3]

for dataset, demographic_cols in zip(dataframes, demographic_cols):
    print(dataset, demographic_cols)