Files
drift/feature_selection/feature_selection.py
T
Mark Aron Szulyovszky 1856fcad22 feat(Transformations): added Transformations abstraction & handling in walk_forward_train() & inference() (#161)
* feat(Transformations): added Transformations abstraction & handling in walk_forward_train() & inference()

* fix(WalkForward): use Dataframes to call Transformation.fit_transform()

* feat(WalkForward): restored option for models to recieve unscaled data

* fix(Transformations): output DataFrame as expected

* fix(Tests): missing new property
2022-01-12 23:22:55 +01:00

41 lines
1.8 KiB
Python

from sklearn.feature_selection import RFE
from sklearn.model_selection import TimeSeriesSplit
import pandas as pd
from models.base import Model
from models.sklearn import SKLearnModel
from utils.scaler import get_scaler
from utils.types import ScalerTypes
# from utils.hashing import hash_df, hash_series
# from diskcache import Cache
# cache = Cache(".cachedir/feature_selection")
# def select_features(**kwargs) -> pd.DataFrame:
# hashed = kwargs['data_config_hash'] + kwargs['model'].get_name() + str(kwargs['n_features_to_select']) + kwargs['backup_model'].get_name() + kwargs['scaling']
# if hashed in cache:
# return cache.get(hashed)
# else:
# return_value = __select_features(**kwargs)
# cache[hashed] = return_value
# return return_value
def select_features(X: pd.DataFrame, y: pd.Series, model: Model, n_features_to_select: int, backup_model: SKLearnModel, scaling: ScalerTypes) -> pd.DataFrame:
''' Select features using RFECV, returns a pd.DataFrame (X) with only the selected features.'''
if model.model_type != 'ml': return X
# 2. Recursive feature selection
cv = TimeSeriesSplit(n_splits=5)
scaler = get_scaler(scaling)
X_scaled = scaler.fit_transform(X, y)
feat_selector_model = model.model
if hasattr(feat_selector_model, 'feature_importances_') == False and hasattr(feat_selector_model, 'coef_') == False:
feat_selector_model = backup_model.model
# selector = RFECV(feat_selector_model, cv = cv, step=5, min_features_to_select=min_features_to_select)
step = 0.05
selector = RFE(feat_selector_model, n_features_to_select= n_features_to_select, step=step)
selector = selector.fit(X_scaled, y)
print("Kept %d features out of %d" % (selector.n_features_, X_scaled.shape[1]))
return pd.DataFrame(X[X.columns[selector.support_]], index= X.index)