def test_default_parameters(df_test):
X, y = df_test
sel = SelectBySingleFeaturePerformance(
RandomForestClassifier(random_state=1))
sel.fit(X, y)
# expected result
Xtransformed = X.copy()
Xtransformed.drop("var_3", 1, inplace=True)
Xtransformed.drop("var_10", 1, inplace=True)
# test init params
assert sel.variables == [
"var_0",
"var_1",
"var_2",
"var_3",
"var_4",
"var_5",
"var_6",
"var_7",
"var_8",
"var_9",
"var_10",
"var_11",
]
assert sel.threshold == 0.5
assert sel.cv == 3
assert sel.scoring == "roc_auc"
# test fit attrs
assert sel.selected_features_ == [
"var_0",
"var_1",
"var_2",
"var_4",
"var_5",
"var_6",
"var_7",
"var_8",
"var_9",
"var_11",
]
assert sel.feature_performance_ == {
"var_0": 0.5957642619540211,
"var_1": 0.5365534287221033,
"var_2": 0.5001855546283257,
"var_3": 0.4752954458526748,
"var_4": 0.9780875304971691,
"var_5": 0.5065441419357082,
"var_6": 0.9758243290622809,
"var_7": 0.994571685008432,
"var_8": 0.5164434795458892,
"var_9": 0.9543427678969847,
"var_10": 0.47404183834906727,
"var_11": 0.5227164067525513,
}
# test transform output
pd.testing.assert_frame_equal(sel.transform(X), Xtransformed)
def test_regression_cv_2_and_mse(load_diabetes_dataset):
# test for regression using cv=2, and the neg_mean_squared_error as metric.
# add suitable threshold for regression mse
X, y = load_diabetes_dataset
sel = SelectBySingleFeaturePerformance(
estimator=DecisionTreeRegressor(random_state=0),
scoring="neg_mean_squared_error",
cv=2,
threshold=10,
)
# fit transformer
sel.fit(X, y)
# expected output
Xtransformed = X.copy()
Xtransformed.drop(
Xtransformed.columns[[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]], axis=1, inplace=True
)
# test init params
assert sel.cv == 2
assert sel.variables == list(X.columns)
assert sel.scoring == "neg_mean_squared_error"
assert sel.threshold == 10
# fit params
assert sel.selected_features_ == []
assert sel.feature_performance_ == {
0: -7657.154138192973,
1: -5966.662211695372,
2: -6613.779604700854,
3: -6502.621725718592,
4: -9415.586278197177,
5: -11760.999622926094,
6: -6592.584431571728,
7: -5270.563893676307,
8: -7641.414795123177,
9: -6287.557824391035,
}
# test transform output
print(sel.transform(X))
pd.testing.assert_frame_equal(sel.transform(X), Xtransformed)
def test_automatic_variable_selection(df_test):
X, y = df_test
# add 2 additional categorical variables, these should not be evaluated by
# the selector
X["cat_1"] = "cat1"
X["cat_2"] = "cat2"
sel = SelectBySingleFeaturePerformance(
RandomForestClassifier(random_state=1), threshold=0.5
)
sel.fit(X, y)
# expected result
Xtransformed = X.copy()
Xtransformed.drop(columns=["var_3", "var_10"], inplace=True)
# test init params
assert sel.variables is None
assert sel.threshold == 0.5
assert sel.cv == 3
assert sel.scoring == "roc_auc"
# test fit attrs
assert sel.variables_ == [
"var_0",
"var_1",
"var_2",
"var_3",
"var_4",
"var_5",
"var_6",
"var_7",
"var_8",
"var_9",
"var_10",
"var_11",
]
assert sel.features_to_drop_ == ["var_3", "var_10"]
assert sel.feature_performance_ == {
"var_0": 0.5957642619540211,
"var_1": 0.5365534287221033,
"var_2": 0.5001855546283257,
"var_3": 0.4752954458526748,
"var_4": 0.9780875304971691,
"var_5": 0.5065441419357082,
"var_6": 0.9758243290622809,
"var_7": 0.994571685008432,
"var_8": 0.5164434795458892,
"var_9": 0.9543427678969847,
"var_10": 0.47404183834906727,
"var_11": 0.5227164067525513,
}
# test transform output
pd.testing.assert_frame_equal(sel.transform(X), Xtransformed)
def test_regression_cv_3_and_r2(load_diabetes_dataset):
# test for regression using cv=3, and the r2 as metric.
X, y = load_diabetes_dataset
sel = SelectBySingleFeaturePerformance(
estimator=LinearRegression(), scoring="r2", cv=3, threshold=0.01
)
sel.fit(X, y)
# expected output
Xtransformed = pd.DataFrame(X[[0, 2, 3, 4, 5, 6, 7, 8, 9]].copy())
performance_dict = {
0: 0.029,
1: -0.004,
2: 0.337,
3: 0.192,
4: 0.037,
5: 0.018,
6: 0.152,
7: 0.177,
8: 0.315,
9: 0.139,
}
# test init params
assert sel.cv == 3
assert sel.variables is None
assert sel.scoring == "r2"
assert sel.threshold == 0.01
# fit params
assert sel.variables_ == list(X.columns)
assert sel.features_to_drop_ == [1]
assert all(
np.round(sel.feature_performance_[f], 3) == performance_dict[f]
for f in sel.feature_performance_.keys()
)
# test transform output
pd.testing.assert_frame_equal(sel.transform(X), Xtransformed)
def test_non_fitted_error(df_test):
# when fit is not called prior to transform
with pytest.raises(NotFittedError):
sel = SelectBySingleFeaturePerformance()
sel.transform(df_test)
def test_KFold_generators(df_test):
X, y = df_test
# Kfold
sel = SelectBySingleFeaturePerformance(
RandomForestClassifier(random_state=1),
threshold=0.5,
cv=KFold(n_splits=3),
)
sel.fit(X, y)
Xtransformed = sel.transform(X)
# test fit attrs
assert isinstance(sel.features_to_drop_, list)
assert all([x for x in sel.features_to_drop_ if x in X.columns])
assert len(sel.features_to_drop_) < X.shape[1]
assert not Xtransformed.empty
assert all([x for x in Xtransformed.columns if x not in sel.features_to_drop_])
assert isinstance(sel.feature_performance_, dict)
assert all([x for x in X.columns if x in sel.feature_performance_.keys()])
assert all(
[
isinstance(sel.feature_performance_[var], float)
for var in sel.feature_performance_.keys()
]
)
# Stratfied
sel = SelectBySingleFeaturePerformance(
RandomForestClassifier(random_state=1),
threshold=0.5,
cv=StratifiedKFold(n_splits=3),
)
sel.fit(X, y)
Xtransformed = sel.transform(X)
# test fit attrs
assert isinstance(sel.features_to_drop_, list)
assert all([x for x in sel.features_to_drop_ if x in X.columns])
assert len(sel.features_to_drop_) < X.shape[1]
assert not Xtransformed.empty
assert all([x for x in Xtransformed.columns if x not in sel.features_to_drop_])
assert isinstance(sel.feature_performance_, dict)
assert all([x for x in X.columns if x in sel.feature_performance_.keys()])
assert all(
[
isinstance(sel.feature_performance_[var], float)
for var in sel.feature_performance_.keys()
]
)
# None
sel = SelectBySingleFeaturePerformance(
RandomForestClassifier(random_state=1),
threshold=0.5,
cv=None,
)
sel.fit(X, y)
Xtransformed = sel.transform(X)
# test fit attrs
assert isinstance(sel.features_to_drop_, list)
assert all([x for x in sel.features_to_drop_ if x in X.columns])
assert len(sel.features_to_drop_) < X.shape[1]
assert not Xtransformed.empty
assert all([x for x in Xtransformed.columns if x not in sel.features_to_drop_])
assert isinstance(sel.feature_performance_, dict)
assert all([x for x in X.columns if x in sel.feature_performance_.keys()])
assert all(
[
isinstance(sel.feature_performance_[var], float)
for var in sel.feature_performance_.keys()
]
)
def test_non_fitted_error(df_test):
# when fit is not called prior to transform
with pytest.raises(NotFittedError):
sel = SelectBySingleFeaturePerformance(RandomForestClassifier(random_state=1))
sel.transform(df_test)