Convert categorical data in pandas dataframe

Question

I have a dataframe with this type of data (too many columns):

col1        int64
col2        int64
col3        category
col4        category
col5        categ         


        

Answer 1

Here multiple columns need to be converted. So, one approach i used is ..

for col_name in df.columns:
    if(df[col_name].dtype == 'object'):
        df[col_name]= df[col_name].astype('category')
        df[col_name] = df[col_name].cat.codes

This converts all string / object type columns to categorical. Then applies codes to each type of category.