LookupTransformer example

LookupTransformer.py

from sklearn.compose import ColumnTransformer
from sklearn.preprocessing import OneHotEncoder, LabelBinarizer
from sklearn_pandas import DataFrameMapper

col_trans2 = ColumnTransformer([('first', 'drop', [0])]
                               , remainder='passthrough', sparse_threshold=0.0)

mapper = DataFrameMapper([
  ('code1', [CategoricalDomain(missing_value_treatment = "as_value", missing_value_replacement = '!')
             ,LookupTransformer({'a': 'b', 'b': 'd', 'c': 'd'}, 'a')
             , LabelBinarizer(), col_trans2])
])