def test_sparse_regression():
"""Check regression for various parameter settings on sparse input."""
rng = check_random_state(0)
X_train, X_test, y_train, y_test = train_test_split(boston.data[:50],
boston.target[:50],
random_state=rng)
class CustomSVR(SVR):
"""SVC variant that records the nature of the training set"""
def fit(self, X, y):
super(CustomSVR, self).fit(X, y)
self.data_type_ = type(X)
return self
parameter_sets = [
{"max_samples": 0.5,
"max_features": 2,
"bootstrap": True,
"bootstrap_features": True},
{"max_samples": 1.0,
"max_features": 4,
"bootstrap": True,
"bootstrap_features": True},
{"max_features": 2,
"bootstrap": False,
"bootstrap_features": True},
{"max_samples": 0.5,
"bootstrap": True,
"bootstrap_features": False},
]
for sparse_format in [csc_matrix, csr_matrix]:
X_train_sparse = sparse_format(X_train)
X_test_sparse = sparse_format(X_test)
for params in parameter_sets:
# Trained on sparse format
sparse_classifier = LazyBaggingRegressor(
base_estimator=CustomSVR(),
random_state=1,
**params
).fit(X_train_sparse, y_train)
sparse_results = sparse_classifier.predict(X_test_sparse)
# Trained on dense format
dense_results = LazyBaggingRegressor(
base_estimator=CustomSVR(),
random_state=1,
**params
).fit(X_train, y_train).predict(X_test)
sparse_type = type(X_train_sparse)
types = [i.data_type_ for i in sparse_classifier.estimators_]
assert_array_equal(sparse_results, dense_results)
assert all([t == sparse_type for t in types])
assert_array_equal(sparse_results, dense_results)
def test_single_estimator():
"""Check singleton ensembles."""
rng = check_random_state(0)
X_train, X_test, y_train, y_test = train_test_split(boston.data,
boston.target,
random_state=rng)
clf1 = LazyBaggingRegressor(base_estimator=KNeighborsRegressor(),
n_estimators=1,
bootstrap=False,
bootstrap_features=False,
random_state=rng).fit(X_train, y_train)
clf2 = KNeighborsRegressor().fit(X_train, y_train)
assert_array_equal(clf1.predict(X_test), clf2.predict(X_test))
