xgboost/tests/python/test_with_sklearn.py
Jiaming Yuan 52d4eda786
Deprecate use_label_encoder in XGBClassifier. (#7822)
* Deprecate `use_label_encoder` in XGBClassifier.

* We have removed the encoder, now prepare to remove the indicator.
2022-04-21 13:14:02 +08:00

1364 lines
46 KiB
Python

from typing import Callable, Optional
import collections
import importlib.util
import numpy as np
import xgboost as xgb
import testing as tm
import tempfile
import os
import shutil
import pytest
import json
rng = np.random.RandomState(1994)
pytestmark = pytest.mark.skipif(**tm.no_sklearn())
from sklearn.utils.estimator_checks import parametrize_with_checks
def test_binary_classification():
from sklearn.datasets import load_digits
from sklearn.model_selection import KFold
digits = load_digits(n_class=2)
y = digits['target']
X = digits['data']
kf = KFold(n_splits=2, shuffle=True, random_state=rng)
for cls in (xgb.XGBClassifier, xgb.XGBRFClassifier):
for train_index, test_index in kf.split(X, y):
clf = cls(random_state=42)
xgb_model = clf.fit(X[train_index], y[train_index], eval_metric=['auc', 'logloss'])
preds = xgb_model.predict(X[test_index])
labels = y[test_index]
err = sum(1 for i in range(len(preds))
if int(preds[i] > 0.5) != labels[i]) / float(len(preds))
assert err < 0.1
@pytest.mark.parametrize('objective', ['multi:softmax', 'multi:softprob'])
def test_multiclass_classification(objective):
from sklearn.datasets import load_iris
from sklearn.model_selection import KFold
def check_pred(preds, labels, output_margin):
if output_margin:
err = sum(1 for i in range(len(preds))
if preds[i].argmax() != labels[i]) / float(len(preds))
else:
err = sum(1 for i in range(len(preds))
if preds[i] != labels[i]) / float(len(preds))
assert err < 0.4
iris = load_iris()
y = iris['target']
X = iris['data']
kf = KFold(n_splits=2, shuffle=True, random_state=rng)
for train_index, test_index in kf.split(X, y):
xgb_model = xgb.XGBClassifier(objective=objective).fit(X[train_index], y[train_index])
assert (xgb_model.get_booster().num_boosted_rounds() ==
xgb_model.n_estimators)
preds = xgb_model.predict(X[test_index])
# test other params in XGBClassifier().fit
preds2 = xgb_model.predict(X[test_index], output_margin=True,
ntree_limit=3)
preds3 = xgb_model.predict(X[test_index], output_margin=True,
ntree_limit=0)
preds4 = xgb_model.predict(X[test_index], output_margin=False,
ntree_limit=3)
labels = y[test_index]
check_pred(preds, labels, output_margin=False)
check_pred(preds2, labels, output_margin=True)
check_pred(preds3, labels, output_margin=True)
check_pred(preds4, labels, output_margin=False)
cls = xgb.XGBClassifier(n_estimators=4).fit(X, y)
assert cls.n_classes_ == 3
proba = cls.predict_proba(X)
assert proba.shape[0] == X.shape[0]
assert proba.shape[1] == cls.n_classes_
# custom objective, the default is multi:softprob so no transformation is required.
cls = xgb.XGBClassifier(n_estimators=4, objective=tm.softprob_obj(3)).fit(X, y)
proba = cls.predict_proba(X)
assert proba.shape[0] == X.shape[0]
assert proba.shape[1] == cls.n_classes_
def test_best_ntree_limit():
from sklearn.datasets import load_iris
X, y = load_iris(return_X_y=True)
def train(booster, forest):
rounds = 4
cls = xgb.XGBClassifier(
n_estimators=rounds, num_parallel_tree=forest, booster=booster
).fit(
X, y, eval_set=[(X, y)], early_stopping_rounds=3
)
if forest:
assert cls.best_ntree_limit == rounds * forest
else:
assert cls.best_ntree_limit == 0
# best_ntree_limit is used by default, assert that under gblinear it's
# automatically ignored due to being 0.
cls.predict(X)
num_parallel_tree = 4
train('gbtree', num_parallel_tree)
train('dart', num_parallel_tree)
train('gblinear', None)
def test_ranking():
# generate random data
x_train = np.random.rand(1000, 10)
y_train = np.random.randint(5, size=1000)
train_group = np.repeat(50, 20)
x_valid = np.random.rand(200, 10)
y_valid = np.random.randint(5, size=200)
valid_group = np.repeat(50, 4)
x_test = np.random.rand(100, 10)
params = {'tree_method': 'exact', 'objective': 'rank:pairwise',
'learning_rate': 0.1, 'gamma': 1.0, 'min_child_weight': 0.1,
'max_depth': 6, 'n_estimators': 4}
model = xgb.sklearn.XGBRanker(**params)
model.fit(x_train, y_train, group=train_group,
eval_set=[(x_valid, y_valid)], eval_group=[valid_group])
assert model.evals_result()
pred = model.predict(x_test)
train_data = xgb.DMatrix(x_train, y_train)
valid_data = xgb.DMatrix(x_valid, y_valid)
test_data = xgb.DMatrix(x_test)
train_data.set_group(train_group)
assert train_data.get_label().shape[0] == x_train.shape[0]
valid_data.set_group(valid_group)
params_orig = {'tree_method': 'exact', 'objective': 'rank:pairwise',
'eta': 0.1, 'gamma': 1.0,
'min_child_weight': 0.1, 'max_depth': 6}
xgb_model_orig = xgb.train(params_orig, train_data, num_boost_round=4,
evals=[(valid_data, 'validation')])
pred_orig = xgb_model_orig.predict(test_data)
np.testing.assert_almost_equal(pred, pred_orig)
def test_stacking_regression():
from sklearn.model_selection import train_test_split
from sklearn.datasets import load_diabetes
from sklearn.linear_model import RidgeCV
from sklearn.ensemble import RandomForestRegressor
from sklearn.ensemble import StackingRegressor
X, y = load_diabetes(return_X_y=True)
estimators = [
('gbm', xgb.sklearn.XGBRegressor(objective='reg:squarederror')),
('lr', RidgeCV())
]
reg = StackingRegressor(
estimators=estimators,
final_estimator=RandomForestRegressor(n_estimators=10,
random_state=42)
)
X_train, X_test, y_train, y_test = train_test_split(X, y, random_state=42)
reg.fit(X_train, y_train).score(X_test, y_test)
def test_stacking_classification():
from sklearn.model_selection import train_test_split
from sklearn.datasets import load_iris
from sklearn.svm import LinearSVC
from sklearn.linear_model import LogisticRegression
from sklearn.preprocessing import StandardScaler
from sklearn.pipeline import make_pipeline
from sklearn.ensemble import StackingClassifier
X, y = load_iris(return_X_y=True)
estimators = [
('gbm', xgb.sklearn.XGBClassifier()),
('svr', make_pipeline(StandardScaler(),
LinearSVC(random_state=42)))
]
clf = StackingClassifier(
estimators=estimators, final_estimator=LogisticRegression()
)
X_train, X_test, y_train, y_test = train_test_split(X, y, random_state=42)
clf.fit(X_train, y_train).score(X_test, y_test)
@pytest.mark.skipif(**tm.no_pandas())
def test_feature_importances_weight():
from sklearn.datasets import load_digits
digits = load_digits(n_class=2)
y = digits['target']
X = digits['data']
xgb_model = xgb.XGBClassifier(random_state=0,
tree_method="exact",
learning_rate=0.1,
importance_type="weight").fit(X, y)
exp = np.array([0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.00833333, 0.,
0., 0., 0., 0., 0., 0., 0., 0.025, 0.14166667, 0., 0., 0.,
0., 0., 0., 0.00833333, 0.25833333, 0., 0., 0., 0.,
0.03333334, 0.03333334, 0., 0.32499999, 0., 0., 0., 0.,
0.05, 0.06666667, 0., 0., 0., 0., 0., 0., 0., 0.04166667,
0., 0., 0., 0., 0., 0., 0., 0.00833333, 0., 0., 0., 0.,
0.], dtype=np.float32)
np.testing.assert_almost_equal(xgb_model.feature_importances_, exp)
# numeric columns
import pandas as pd
y = pd.Series(digits['target'])
X = pd.DataFrame(digits['data'])
xgb_model = xgb.XGBClassifier(random_state=0,
tree_method="exact",
learning_rate=0.1,
importance_type="weight").fit(X, y)
np.testing.assert_almost_equal(xgb_model.feature_importances_, exp)
xgb_model = xgb.XGBClassifier(random_state=0,
tree_method="exact",
learning_rate=0.1,
importance_type="weight").fit(X, y)
np.testing.assert_almost_equal(xgb_model.feature_importances_, exp)
with pytest.raises(ValueError):
xgb_model.set_params(importance_type="foo")
xgb_model.feature_importances_
X, y = load_digits(n_class=3, return_X_y=True)
cls = xgb.XGBClassifier(booster="gblinear", n_estimators=4)
cls.fit(X, y)
assert cls.feature_importances_.shape[0] == X.shape[1]
assert cls.feature_importances_.shape[1] == 3
with tempfile.TemporaryDirectory() as tmpdir:
path = os.path.join(tmpdir, "model.json")
cls.save_model(path)
with open(path, "r") as fd:
model = json.load(fd)
weights = np.array(
model["learner"]["gradient_booster"]["model"]["weights"]
).reshape((cls.n_features_in_ + 1, 3))
weights = weights[:-1, ...]
np.testing.assert_allclose(
weights / weights.sum(), cls.feature_importances_, rtol=1e-6
)
with pytest.raises(ValueError):
cls.set_params(importance_type="cover")
cls.feature_importances_
@pytest.mark.skipif(**tm.no_pandas())
def test_feature_importances_gain():
from sklearn.datasets import load_digits
digits = load_digits(n_class=2)
y = digits['target']
X = digits['data']
xgb_model = xgb.XGBClassifier(
random_state=0, tree_method="exact",
learning_rate=0.1,
importance_type="gain",
).fit(X, y)
exp = np.array([0., 0., 0., 0., 0., 0., 0., 0., 0., 0.,
0.00326159, 0., 0., 0., 0., 0., 0., 0., 0.,
0.00297238, 0.00988034, 0., 0., 0., 0., 0., 0.,
0.03512521, 0.41123885, 0., 0., 0., 0.,
0.01326332, 0.00160674, 0., 0.4206952, 0., 0., 0.,
0., 0.00616747, 0.01237546, 0., 0., 0., 0., 0.,
0., 0., 0.08240705, 0., 0., 0., 0., 0., 0., 0.,
0.00100649, 0., 0., 0., 0., 0.], dtype=np.float32)
np.testing.assert_almost_equal(xgb_model.feature_importances_, exp)
# numeric columns
import pandas as pd
y = pd.Series(digits['target'])
X = pd.DataFrame(digits['data'])
xgb_model = xgb.XGBClassifier(
random_state=0,
tree_method="exact",
learning_rate=0.1,
importance_type="gain",
).fit(X, y)
np.testing.assert_almost_equal(xgb_model.feature_importances_, exp)
xgb_model = xgb.XGBClassifier(
random_state=0,
tree_method="exact",
learning_rate=0.1,
importance_type="gain",
).fit(X, y)
np.testing.assert_almost_equal(xgb_model.feature_importances_, exp)
# no split can be found
cls = xgb.XGBClassifier(min_child_weight=1000, tree_method="hist", n_estimators=1)
cls.fit(X, y)
assert np.all(cls.feature_importances_ == 0)
def test_select_feature():
from sklearn.datasets import load_digits
from sklearn.feature_selection import SelectFromModel
digits = load_digits(n_class=2)
y = digits['target']
X = digits['data']
cls = xgb.XGBClassifier()
cls.fit(X, y)
selector = SelectFromModel(cls, prefit=True, max_features=1)
X_selected = selector.transform(X)
assert X_selected.shape[1] == 1
def test_num_parallel_tree():
from sklearn.datasets import fetch_california_housing
reg = xgb.XGBRegressor(n_estimators=4, num_parallel_tree=4, tree_method="hist")
X, y = fetch_california_housing(return_X_y=True)
bst = reg.fit(X=X, y=y)
dump = bst.get_booster().get_dump(dump_format="json")
assert len(dump) == 16
reg = xgb.XGBRFRegressor(n_estimators=4)
bst = reg.fit(X=X, y=y)
dump = bst.get_booster().get_dump(dump_format="json")
assert len(dump) == 4
config = json.loads(bst.get_booster().save_config())
assert (
int(
config["learner"]["gradient_booster"]["gbtree_model_param"][
"num_parallel_tree"
]
)
== 4
)
def test_calif_housing_regression():
from sklearn.metrics import mean_squared_error
from sklearn.datasets import fetch_california_housing
from sklearn.model_selection import KFold
X, y = fetch_california_housing(return_X_y=True)
kf = KFold(n_splits=2, shuffle=True, random_state=rng)
for train_index, test_index in kf.split(X, y):
xgb_model = xgb.XGBRegressor().fit(X[train_index], y[train_index])
preds = xgb_model.predict(X[test_index])
# test other params in XGBRegressor().fit
preds2 = xgb_model.predict(X[test_index], output_margin=True,
ntree_limit=3)
preds3 = xgb_model.predict(X[test_index], output_margin=True,
ntree_limit=0)
preds4 = xgb_model.predict(X[test_index], output_margin=False,
ntree_limit=3)
labels = y[test_index]
assert mean_squared_error(preds, labels) < 25
assert mean_squared_error(preds2, labels) < 350
assert mean_squared_error(preds3, labels) < 25
assert mean_squared_error(preds4, labels) < 350
with pytest.raises(AttributeError, match="feature_names_in_"):
xgb_model.feature_names_in_
def run_calif_housing_rf_regression(tree_method):
from sklearn.metrics import mean_squared_error
from sklearn.datasets import fetch_california_housing
from sklearn.model_selection import KFold
X, y = fetch_california_housing(return_X_y=True)
kf = KFold(n_splits=2, shuffle=True, random_state=rng)
for train_index, test_index in kf.split(X, y):
xgb_model = xgb.XGBRFRegressor(random_state=42, tree_method=tree_method).fit(
X[train_index], y[train_index]
)
preds = xgb_model.predict(X[test_index])
labels = y[test_index]
assert mean_squared_error(preds, labels) < 35
rfreg = xgb.XGBRFRegressor()
with pytest.raises(NotImplementedError):
rfreg.fit(X, y, early_stopping_rounds=10)
def test_calif_housing_rf_regression():
run_calif_housing_rf_regression("hist")
def test_parameter_tuning():
from sklearn.model_selection import GridSearchCV
from sklearn.datasets import fetch_california_housing
X, y = fetch_california_housing(return_X_y=True)
xgb_model = xgb.XGBRegressor(learning_rate=0.1)
clf = GridSearchCV(xgb_model, {'max_depth': [2, 4, 6],
'n_estimators': [50, 100, 200]},
cv=3, verbose=1)
clf.fit(X, y)
assert clf.best_score_ < 0.7
assert clf.best_params_ == {'n_estimators': 200, 'max_depth': 4}
def test_regression_with_custom_objective():
from sklearn.metrics import mean_squared_error
from sklearn.datasets import fetch_california_housing
from sklearn.model_selection import KFold
def objective_ls(y_true, y_pred):
grad = (y_pred - y_true)
hess = np.ones(len(y_true))
return grad, hess
X, y = fetch_california_housing(return_X_y=True)
kf = KFold(n_splits=2, shuffle=True, random_state=rng)
for train_index, test_index in kf.split(X, y):
xgb_model = xgb.XGBRegressor(objective=objective_ls).fit(
X[train_index], y[train_index]
)
preds = xgb_model.predict(X[test_index])
labels = y[test_index]
assert mean_squared_error(preds, labels) < 25
# Test that the custom objective function is actually used
class XGBCustomObjectiveException(Exception):
pass
def dummy_objective(y_true, y_pred):
raise XGBCustomObjectiveException()
xgb_model = xgb.XGBRegressor(objective=dummy_objective)
np.testing.assert_raises(XGBCustomObjectiveException, xgb_model.fit, X, y)
def test_classification_with_custom_objective():
from sklearn.datasets import load_digits
from sklearn.model_selection import KFold
def logregobj(y_true, y_pred):
y_pred = 1.0 / (1.0 + np.exp(-y_pred))
grad = y_pred - y_true
hess = y_pred * (1.0 - y_pred)
return grad, hess
digits = load_digits(n_class=2)
y = digits['target']
X = digits['data']
kf = KFold(n_splits=2, shuffle=True, random_state=rng)
for train_index, test_index in kf.split(X, y):
xgb_model = xgb.XGBClassifier(objective=logregobj)
xgb_model.fit(X[train_index], y[train_index])
preds = xgb_model.predict(X[test_index])
labels = y[test_index]
err = sum(1 for i in range(len(preds))
if int(preds[i] > 0.5) != labels[i]) / float(len(preds))
assert err < 0.1
# Test that the custom objective function is actually used
class XGBCustomObjectiveException(Exception):
pass
def dummy_objective(y_true, y_preds):
raise XGBCustomObjectiveException()
xgb_model = xgb.XGBClassifier(objective=dummy_objective)
np.testing.assert_raises(
XGBCustomObjectiveException,
xgb_model.fit,
X, y
)
cls = xgb.XGBClassifier(n_estimators=1)
cls.fit(X, y)
is_called = [False]
def wrapped(y, p):
is_called[0] = True
return logregobj(y, p)
cls.set_params(objective=wrapped)
cls.predict(X) # no throw
cls.fit(X, y)
assert is_called[0]
def run_sklearn_api(booster, error, n_est):
from sklearn.datasets import load_iris
from sklearn.model_selection import train_test_split
iris = load_iris()
tr_d, te_d, tr_l, te_l = train_test_split(iris.data, iris.target,
train_size=120, test_size=0.2)
classifier = xgb.XGBClassifier(booster=booster, n_estimators=n_est)
classifier.fit(tr_d, tr_l)
preds = classifier.predict(te_d)
labels = te_l
err = sum([1 for p, l in zip(preds, labels) if p != l]) * 1.0 / len(te_l)
assert err < error
def test_sklearn_api():
run_sklearn_api("gbtree", 0.2, 10)
run_sklearn_api("gblinear", 0.5, 100)
@pytest.mark.skipif(**tm.no_matplotlib())
@pytest.mark.skipif(**tm.no_graphviz())
def test_sklearn_plotting():
from sklearn.datasets import load_iris
iris = load_iris()
classifier = xgb.XGBClassifier()
classifier.fit(iris.data, iris.target)
import matplotlib
matplotlib.use('Agg')
from matplotlib.axes import Axes
from graphviz import Source
ax = xgb.plot_importance(classifier)
assert isinstance(ax, Axes)
assert ax.get_title() == 'Feature importance'
assert ax.get_xlabel() == 'F score'
assert ax.get_ylabel() == 'Features'
assert len(ax.patches) == 4
g = xgb.to_graphviz(classifier, num_trees=0)
assert isinstance(g, Source)
ax = xgb.plot_tree(classifier, num_trees=0)
assert isinstance(ax, Axes)
@pytest.mark.skipif(**tm.no_pandas())
def test_sklearn_nfolds_cv():
from sklearn.datasets import load_digits
from sklearn.model_selection import StratifiedKFold
digits = load_digits(n_class=3)
X = digits['data']
y = digits['target']
dm = xgb.DMatrix(X, label=y)
params = {
'max_depth': 2,
'eta': 1,
'verbosity': 0,
'objective':
'multi:softprob',
'num_class': 3
}
seed = 2016
nfolds = 5
skf = StratifiedKFold(n_splits=nfolds, shuffle=True, random_state=seed)
cv1 = xgb.cv(params, dm, num_boost_round=10, nfold=nfolds,
seed=seed, as_pandas=True)
cv2 = xgb.cv(params, dm, num_boost_round=10, nfold=nfolds,
folds=skf, seed=seed, as_pandas=True)
cv3 = xgb.cv(params, dm, num_boost_round=10, nfold=nfolds,
stratified=True, seed=seed, as_pandas=True)
assert cv1.shape[0] == cv2.shape[0] and cv2.shape[0] == cv3.shape[0]
assert cv2.iloc[-1, 0] == cv3.iloc[-1, 0]
@pytest.mark.skipif(**tm.no_pandas())
def test_split_value_histograms():
from sklearn.datasets import load_digits
digits_2class = load_digits(n_class=2)
X = digits_2class['data']
y = digits_2class['target']
dm = xgb.DMatrix(X, label=y)
params = {'max_depth': 6, 'eta': 0.01, 'verbosity': 0,
'objective': 'binary:logistic'}
gbdt = xgb.train(params, dm, num_boost_round=10)
assert gbdt.get_split_value_histogram("not_there",
as_pandas=True).shape[0] == 0
assert gbdt.get_split_value_histogram("not_there",
as_pandas=False).shape[0] == 0
assert gbdt.get_split_value_histogram("f28", bins=0).shape[0] == 1
assert gbdt.get_split_value_histogram("f28", bins=1).shape[0] == 1
assert gbdt.get_split_value_histogram("f28", bins=2).shape[0] == 2
assert gbdt.get_split_value_histogram("f28", bins=5).shape[0] == 2
assert gbdt.get_split_value_histogram("f28", bins=None).shape[0] == 2
def test_sklearn_random_state():
clf = xgb.XGBClassifier(random_state=402)
assert clf.get_xgb_params()['random_state'] == 402
clf = xgb.XGBClassifier(random_state=401)
assert clf.get_xgb_params()['random_state'] == 401
random_state = np.random.RandomState(seed=403)
clf = xgb.XGBClassifier(random_state=random_state)
assert isinstance(clf.get_xgb_params()['random_state'], int)
def test_sklearn_n_jobs():
clf = xgb.XGBClassifier(n_jobs=1)
assert clf.get_xgb_params()['n_jobs'] == 1
clf = xgb.XGBClassifier(n_jobs=2)
assert clf.get_xgb_params()['n_jobs'] == 2
def test_parameters_access():
from sklearn import datasets
params = {'updater': 'grow_gpu_hist', 'subsample': .5, 'n_jobs': -1}
clf = xgb.XGBClassifier(n_estimators=1000, **params)
assert clf.get_params()['updater'] == 'grow_gpu_hist'
assert clf.get_params()['subsample'] == .5
assert clf.get_params()['n_estimators'] == 1000
clf = xgb.XGBClassifier(n_estimators=1, nthread=4)
X, y = datasets.load_iris(return_X_y=True)
clf.fit(X, y)
config = json.loads(clf.get_booster().save_config())
assert int(config['learner']['generic_param']['nthread']) == 4
clf.set_params(nthread=16)
config = json.loads(clf.get_booster().save_config())
assert int(config['learner']['generic_param']['nthread']) == 16
clf.predict(X)
config = json.loads(clf.get_booster().save_config())
assert int(config['learner']['generic_param']['nthread']) == 16
def test_kwargs_error():
params = {'updater': 'grow_gpu_hist', 'subsample': .5, 'n_jobs': -1}
with pytest.raises(TypeError):
clf = xgb.XGBClassifier(n_jobs=1000, **params)
assert isinstance(clf, xgb.XGBClassifier)
def test_kwargs_grid_search():
from sklearn.model_selection import GridSearchCV
from sklearn import datasets
params = {'tree_method': 'hist'}
clf = xgb.XGBClassifier(n_estimators=1, learning_rate=1.0, **params)
assert clf.get_params()['tree_method'] == 'hist'
# 'max_leaves' is not a default argument of XGBClassifier
# Check we can still do grid search over this parameter
search_params = {'max_leaves': range(2, 5)}
grid_cv = GridSearchCV(clf, search_params, cv=5)
iris = datasets.load_iris()
grid_cv.fit(iris.data, iris.target)
# Expect unique results for each parameter value
# This confirms sklearn is able to successfully update the parameter
means = grid_cv.cv_results_['mean_test_score']
assert len(means) == len(set(means))
def test_sklearn_clone():
from sklearn.base import clone
clf = xgb.XGBClassifier(n_jobs=2)
clf.n_jobs = -1
clone(clf)
def test_sklearn_get_default_params():
from sklearn.datasets import load_digits
digits_2class = load_digits(n_class=2)
X = digits_2class['data']
y = digits_2class['target']
cls = xgb.XGBClassifier()
assert cls.get_params()['base_score'] is None
cls.fit(X[:4, ...], y[:4, ...])
assert cls.get_params()['base_score'] is not None
def run_validation_weights(model):
from sklearn.datasets import make_hastie_10_2
# prepare training and test data
X, y = make_hastie_10_2(n_samples=2000, random_state=42)
labels, y = np.unique(y, return_inverse=True)
X_train, X_test = X[:1600], X[1600:]
y_train, y_test = y[:1600], y[1600:]
# instantiate model
param_dist = {'objective': 'binary:logistic', 'n_estimators': 2,
'random_state': 123}
clf = model(**param_dist)
# train it using instance weights only in the training set
weights_train = np.random.choice([1, 2], len(X_train))
clf.fit(X_train, y_train,
sample_weight=weights_train,
eval_set=[(X_test, y_test)],
eval_metric='logloss',
verbose=False)
# evaluate logloss metric on test set *without* using weights
evals_result_without_weights = clf.evals_result()
logloss_without_weights = evals_result_without_weights[
"validation_0"]["logloss"]
# now use weights for the test set
np.random.seed(0)
weights_test = np.random.choice([1, 2], len(X_test))
clf.fit(X_train, y_train,
sample_weight=weights_train,
eval_set=[(X_test, y_test)],
sample_weight_eval_set=[weights_test],
eval_metric='logloss',
verbose=False)
evals_result_with_weights = clf.evals_result()
logloss_with_weights = evals_result_with_weights["validation_0"]["logloss"]
# check that the logloss in the test set is actually different when using
# weights than when not using them
assert all((logloss_with_weights[i] != logloss_without_weights[i]
for i in [0, 1]))
with pytest.raises(ValueError):
# length of eval set and sample weight doesn't match.
clf.fit(X_train, y_train, sample_weight=weights_train,
eval_set=[(X_train, y_train), (X_test, y_test)],
sample_weight_eval_set=[weights_train])
with pytest.raises(ValueError):
cls = xgb.XGBClassifier()
cls.fit(X_train, y_train, sample_weight=weights_train,
eval_set=[(X_train, y_train), (X_test, y_test)],
sample_weight_eval_set=[weights_train])
def test_validation_weights():
run_validation_weights(xgb.XGBModel)
run_validation_weights(xgb.XGBClassifier)
def save_load_model(model_path):
from sklearn.datasets import load_digits
from sklearn.model_selection import KFold
digits = load_digits(n_class=2)
y = digits['target']
X = digits['data']
kf = KFold(n_splits=2, shuffle=True, random_state=rng)
for train_index, test_index in kf.split(X, y):
xgb_model = xgb.XGBClassifier().fit(X[train_index], y[train_index])
xgb_model.save_model(model_path)
xgb_model = xgb.XGBClassifier()
xgb_model.load_model(model_path)
assert isinstance(xgb_model.classes_, np.ndarray)
assert isinstance(xgb_model._Booster, xgb.Booster)
preds = xgb_model.predict(X[test_index])
labels = y[test_index]
err = sum(1 for i in range(len(preds))
if int(preds[i] > 0.5) != labels[i]) / float(len(preds))
assert err < 0.1
assert xgb_model.get_booster().attr('scikit_learn') is None
# test native booster
preds = xgb_model.predict(X[test_index], output_margin=True)
booster = xgb.Booster(model_file=model_path)
predt_1 = booster.predict(xgb.DMatrix(X[test_index]),
output_margin=True)
assert np.allclose(preds, predt_1)
with pytest.raises(TypeError):
xgb_model = xgb.XGBModel()
xgb_model.load_model(model_path)
def test_save_load_model():
with tempfile.TemporaryDirectory() as tempdir:
model_path = os.path.join(tempdir, 'digits.model')
save_load_model(model_path)
with tempfile.TemporaryDirectory() as tempdir:
model_path = os.path.join(tempdir, 'digits.model.json')
save_load_model(model_path)
from sklearn.datasets import load_digits
with tempfile.TemporaryDirectory() as tempdir:
model_path = os.path.join(tempdir, 'digits.model.json')
digits = load_digits(n_class=2)
y = digits['target']
X = digits['data']
booster = xgb.train({'tree_method': 'hist',
'objective': 'binary:logistic'},
dtrain=xgb.DMatrix(X, y),
num_boost_round=4)
predt_0 = booster.predict(xgb.DMatrix(X))
booster.save_model(model_path)
cls = xgb.XGBClassifier()
cls.load_model(model_path)
proba = cls.predict_proba(X)
assert proba.shape[0] == X.shape[0]
assert proba.shape[1] == 2 # binary
predt_1 = cls.predict_proba(X)[:, 1]
assert np.allclose(predt_0, predt_1)
cls = xgb.XGBModel()
cls.load_model(model_path)
predt_1 = cls.predict(X)
assert np.allclose(predt_0, predt_1)
def test_RFECV():
from sklearn.datasets import fetch_california_housing
from sklearn.datasets import load_breast_cancer
from sklearn.datasets import load_iris
from sklearn.feature_selection import RFECV
# Regression
X, y = fetch_california_housing(return_X_y=True)
bst = xgb.XGBRegressor(booster='gblinear', learning_rate=0.1,
n_estimators=10,
objective='reg:squarederror',
random_state=0, verbosity=0)
rfecv = RFECV(
estimator=bst, step=1, cv=3, scoring='neg_mean_squared_error')
rfecv.fit(X, y)
# Binary classification
X, y = load_breast_cancer(return_X_y=True)
bst = xgb.XGBClassifier(booster='gblinear', learning_rate=0.1,
n_estimators=10,
objective='binary:logistic',
random_state=0, verbosity=0)
rfecv = RFECV(estimator=bst, step=1, cv=3, scoring='roc_auc')
rfecv.fit(X, y)
# Multi-class classification
X, y = load_iris(return_X_y=True)
bst = xgb.XGBClassifier(base_score=0.4, booster='gblinear',
learning_rate=0.1,
n_estimators=10,
objective='multi:softprob',
random_state=0, reg_alpha=0.001, reg_lambda=0.01,
scale_pos_weight=0.5, verbosity=0)
rfecv = RFECV(estimator=bst, step=1, cv=3, scoring='neg_log_loss')
rfecv.fit(X, y)
X[0:4, :] = np.nan # verify scikit_learn doesn't throw with nan
reg = xgb.XGBRegressor()
rfecv = RFECV(estimator=reg)
rfecv.fit(X, y)
cls = xgb.XGBClassifier()
rfecv = RFECV(estimator=cls, step=1, cv=3,
scoring='neg_mean_squared_error')
rfecv.fit(X, y)
def test_XGBClassifier_resume():
from sklearn.datasets import load_breast_cancer
from sklearn.metrics import log_loss
with tempfile.TemporaryDirectory() as tempdir:
model1_path = os.path.join(tempdir, 'test_XGBClassifier.model')
model1_booster_path = os.path.join(tempdir, 'test_XGBClassifier.booster')
X, Y = load_breast_cancer(return_X_y=True)
model1 = xgb.XGBClassifier(
learning_rate=0.3, random_state=0, n_estimators=8)
model1.fit(X, Y)
pred1 = model1.predict(X)
log_loss1 = log_loss(pred1, Y)
# file name of stored xgb model
model1.save_model(model1_path)
model2 = xgb.XGBClassifier(
learning_rate=0.3, random_state=0, n_estimators=8)
model2.fit(X, Y, xgb_model=model1_path)
pred2 = model2.predict(X)
log_loss2 = log_loss(pred2, Y)
assert np.any(pred1 != pred2)
assert log_loss1 > log_loss2
# file name of 'Booster' instance Xgb model
model1.get_booster().save_model(model1_booster_path)
model2 = xgb.XGBClassifier(
learning_rate=0.3, random_state=0, n_estimators=8)
model2.fit(X, Y, xgb_model=model1_booster_path)
pred2 = model2.predict(X)
log_loss2 = log_loss(pred2, Y)
assert np.any(pred1 != pred2)
assert log_loss1 > log_loss2
def test_constraint_parameters():
reg = xgb.XGBRegressor(interaction_constraints='[[0, 1], [2, 3, 4]]')
X = np.random.randn(10, 10)
y = np.random.randn(10)
reg.fit(X, y)
config = json.loads(reg.get_booster().save_config())
assert config['learner']['gradient_booster']['updater']['grow_colmaker'][
'train_param']['interaction_constraints'] == '[[0, 1], [2, 3, 4]]'
def test_parameter_validation():
reg = xgb.XGBRegressor(foo='bar', verbosity=1)
X = np.random.randn(10, 10)
y = np.random.randn(10)
with tm.captured_output() as (out, err):
reg.fit(X, y)
output = out.getvalue().strip()
assert output.find('foo') != -1
reg = xgb.XGBRegressor(n_estimators=2, missing=3,
importance_type='gain', verbosity=1)
X = np.random.randn(10, 10)
y = np.random.randn(10)
with tm.captured_output() as (out, err):
reg.fit(X, y)
output = out.getvalue().strip()
assert len(output) == 0
def test_deprecate_position_arg():
from sklearn.datasets import load_digits
X, y = load_digits(return_X_y=True, n_class=2)
w = y
with pytest.warns(FutureWarning):
xgb.XGBRegressor(3, learning_rate=0.1)
model = xgb.XGBRegressor(n_estimators=1)
with pytest.warns(FutureWarning):
model.fit(X, y, w)
with pytest.warns(FutureWarning):
xgb.XGBClassifier(1)
model = xgb.XGBClassifier(n_estimators=1)
with pytest.warns(FutureWarning):
model.fit(X, y, w)
with pytest.warns(FutureWarning):
xgb.XGBRanker('rank:ndcg', learning_rate=0.1)
model = xgb.XGBRanker(n_estimators=1)
group = np.repeat(1, X.shape[0])
with pytest.warns(FutureWarning):
model.fit(X, y, group)
with pytest.warns(FutureWarning):
xgb.XGBRFRegressor(1, learning_rate=0.1)
model = xgb.XGBRFRegressor(n_estimators=1)
with pytest.warns(FutureWarning):
model.fit(X, y, w)
model = xgb.XGBRFClassifier(n_estimators=1)
with pytest.warns(FutureWarning):
model.fit(X, y, w)
@pytest.mark.skipif(**tm.no_pandas())
def test_pandas_input():
import pandas as pd
from sklearn.calibration import CalibratedClassifierCV
rng = np.random.RandomState(1994)
kRows = 100
kCols = 6
X = rng.randint(low=0, high=2, size=kRows*kCols)
X = X.reshape(kRows, kCols)
df = pd.DataFrame(X)
feature_names = []
for i in range(1, kCols):
feature_names += ['k'+str(i)]
df.columns = ['status'] + feature_names
target = df['status']
train = df.drop(columns=['status'])
model = xgb.XGBClassifier()
model.fit(train, target)
np.testing.assert_equal(model.feature_names_in_, np.array(feature_names))
clf_isotonic = CalibratedClassifierCV(model,
cv='prefit', method='isotonic')
clf_isotonic.fit(train, target)
assert isinstance(clf_isotonic.calibrated_classifiers_[0].base_estimator,
xgb.XGBClassifier)
np.testing.assert_allclose(np.array(clf_isotonic.classes_),
np.array([0, 1]))
def run_feature_weights(X, y, fw, tree_method, model=xgb.XGBRegressor):
with tempfile.TemporaryDirectory() as tmpdir:
colsample_bynode = 0.5
reg = model(tree_method=tree_method, colsample_bynode=colsample_bynode)
reg.fit(X, y, feature_weights=fw)
model_path = os.path.join(tmpdir, 'model.json')
reg.save_model(model_path)
with open(model_path) as fd:
model = json.load(fd)
parser_path = os.path.join(tm.PROJECT_ROOT, 'demo', 'json-model',
'json_parser.py')
spec = importlib.util.spec_from_file_location("JsonParser",
parser_path)
foo = importlib.util.module_from_spec(spec)
spec.loader.exec_module(foo)
model = foo.Model(model)
splits = {}
total_nodes = 0
for tree in model.trees:
n_nodes = len(tree.nodes)
total_nodes += n_nodes
for n in range(n_nodes):
if tree.is_leaf(n):
continue
if splits.get(tree.split_index(n), None) is None:
splits[tree.split_index(n)] = 1
else:
splits[tree.split_index(n)] += 1
od = collections.OrderedDict(sorted(splits.items()))
tuples = [(k, v) for k, v in od.items()]
k, v = list(zip(*tuples))
w = np.polyfit(k, v, deg=1)
return w
@pytest.mark.parametrize("tree_method", ["approx", "hist"])
def test_feature_weights(tree_method):
kRows = 512
kCols = 64
X = rng.randn(kRows, kCols)
y = rng.randn(kRows)
fw = np.ones(shape=(kCols,))
for i in range(kCols):
fw[i] *= float(i)
poly_increasing = run_feature_weights(X, y, fw, tree_method, xgb.XGBRegressor)
fw = np.ones(shape=(kCols,))
for i in range(kCols):
fw[i] *= float(kCols - i)
poly_decreasing = run_feature_weights(X, y, fw, tree_method, xgb.XGBRegressor)
# Approxmated test, this is dependent on the implementation of random
# number generator in std library.
assert poly_increasing[0] > 0.08
assert poly_decreasing[0] < -0.08
def run_boost_from_prediction_binary(tree_method, X, y, as_frame: Optional[Callable]):
"""
Parameters
----------
as_frame: A callable function to convert margin into DataFrame, useful for different
df implementations.
"""
model_0 = xgb.XGBClassifier(
learning_rate=0.3, random_state=0, n_estimators=4, tree_method=tree_method
)
model_0.fit(X=X, y=y)
margin = model_0.predict(X, output_margin=True)
if as_frame is not None:
margin = as_frame(margin)
model_1 = xgb.XGBClassifier(
learning_rate=0.3, random_state=0, n_estimators=4, tree_method=tree_method
)
model_1.fit(X=X, y=y, base_margin=margin)
predictions_1 = model_1.predict(X, base_margin=margin)
cls_2 = xgb.XGBClassifier(
learning_rate=0.3, random_state=0, n_estimators=8, tree_method=tree_method
)
cls_2.fit(X=X, y=y)
predictions_2 = cls_2.predict(X)
np.testing.assert_allclose(predictions_1, predictions_2)
def run_boost_from_prediction_multi_clasas(
estimator, tree_method, X, y, as_frame: Optional[Callable]
):
# Multi-class
model_0 = estimator(
learning_rate=0.3, random_state=0, n_estimators=4, tree_method=tree_method
)
model_0.fit(X=X, y=y)
margin = model_0.get_booster().inplace_predict(X, predict_type="margin")
if as_frame is not None:
margin = as_frame(margin)
model_1 = estimator(
learning_rate=0.3, random_state=0, n_estimators=4, tree_method=tree_method
)
model_1.fit(X=X, y=y, base_margin=margin)
predictions_1 = model_1.get_booster().predict(
xgb.DMatrix(X, base_margin=margin), output_margin=True
)
model_2 = estimator(
learning_rate=0.3, random_state=0, n_estimators=8, tree_method=tree_method
)
model_2.fit(X=X, y=y)
predictions_2 = model_2.get_booster().inplace_predict(X, predict_type="margin")
if hasattr(predictions_1, "get"):
predictions_1 = predictions_1.get()
if hasattr(predictions_2, "get"):
predictions_2 = predictions_2.get()
np.testing.assert_allclose(predictions_1, predictions_2, atol=1e-6)
@pytest.mark.parametrize("tree_method", ["hist", "approx", "exact"])
def test_boost_from_prediction(tree_method):
from sklearn.datasets import load_breast_cancer, load_digits, make_regression
import pandas as pd
X, y = load_breast_cancer(return_X_y=True)
run_boost_from_prediction_binary(tree_method, X, y, None)
run_boost_from_prediction_binary(tree_method, X, y, pd.DataFrame)
X, y = load_digits(return_X_y=True)
run_boost_from_prediction_multi_clasas(xgb.XGBClassifier, tree_method, X, y, None)
run_boost_from_prediction_multi_clasas(
xgb.XGBClassifier, tree_method, X, y, pd.DataFrame
)
X, y = make_regression(n_samples=100, n_targets=4)
run_boost_from_prediction_multi_clasas(xgb.XGBRegressor, tree_method, X, y, None)
def test_estimator_type():
assert xgb.XGBClassifier._estimator_type == "classifier"
assert xgb.XGBRFClassifier._estimator_type == "classifier"
assert xgb.XGBRegressor._estimator_type == "regressor"
assert xgb.XGBRFRegressor._estimator_type == "regressor"
assert xgb.XGBRanker._estimator_type == "ranker"
from sklearn.datasets import load_digits
X, y = load_digits(n_class=2, return_X_y=True)
cls = xgb.XGBClassifier(n_estimators=2).fit(X, y)
with tempfile.TemporaryDirectory() as tmpdir:
path = os.path.join(tmpdir, "cls.json")
cls.save_model(path)
reg = xgb.XGBRegressor()
with pytest.raises(TypeError):
reg.load_model(path)
cls = xgb.XGBClassifier()
cls.load_model(path) # no error
def test_multilabel_classification() -> None:
from sklearn.datasets import make_multilabel_classification
X, y = make_multilabel_classification(
n_samples=32, n_classes=5, n_labels=3, random_state=0
)
clf = xgb.XGBClassifier(tree_method="hist")
clf.fit(X, y)
booster = clf.get_booster()
learner = json.loads(booster.save_config())["learner"]
assert int(learner["learner_model_param"]["num_target"]) == 5
np.testing.assert_allclose(clf.predict(X), y)
predt = (clf.predict_proba(X) > 0.5).astype(np.int64)
np.testing.assert_allclose(clf.predict(X), predt)
assert predt.dtype == np.int64
def run_data_initialization(DMatrix, model, X, y):
"""Assert that we don't create duplicated DMatrix."""
old_init = DMatrix.__init__
count = [0]
def new_init(self, **kwargs):
count[0] += 1
return old_init(self, **kwargs)
DMatrix.__init__ = new_init
model(n_estimators=1).fit(X, y, eval_set=[(X, y)])
assert count[0] == 1
count[0] = 0 # only 1 DMatrix is created.
y_copy = y.copy()
model(n_estimators=1).fit(X, y, eval_set=[(X, y_copy)])
assert count[0] == 2 # a different Python object is considered different
DMatrix.__init__ = old_init
def test_data_initialization():
from sklearn.datasets import load_digits
X, y = load_digits(return_X_y=True)
run_data_initialization(xgb.DMatrix, xgb.XGBClassifier, X, y)
@parametrize_with_checks([xgb.XGBRegressor()])
def test_estimator_reg(estimator, check):
if os.environ["PYTEST_CURRENT_TEST"].find("check_supervised_y_no_nan") != -1:
# The test uses float64 and requires the error message to contain:
#
# "value too large for dtype(float64)",
#
# while XGBoost stores values as float32. But XGBoost does verify the label
# internally, so we replace this test with custom check.
rng = np.random.RandomState(888)
X = rng.randn(10, 5)
y = np.full(10, np.inf)
with pytest.raises(
ValueError, match="contains NaN, infinity or a value too large"
):
estimator.fit(X, y)
return
if os.environ["PYTEST_CURRENT_TEST"].find("check_estimators_overwrite_params") != -1:
# A hack to pass the scikit-learn parameter mutation tests. XGBoost regressor
# returns actual internal default values for parameters in `get_params`, but those
# are set as `None` in sklearn interface to avoid duplication. So we fit a dummy
# model and obtain the default parameters here for the mutation tests.
from sklearn.datasets import make_regression
X, y = make_regression(n_samples=2, n_features=1)
estimator.set_params(**xgb.XGBRegressor().fit(X, y).get_params())
check(estimator)
def test_prediction_config():
reg = xgb.XGBRegressor()
assert reg._can_use_inplace_predict() is True
reg.set_params(predictor="cpu_predictor")
assert reg._can_use_inplace_predict() is False
reg.set_params(predictor="auto")
assert reg._can_use_inplace_predict() is True
reg.set_params(predictor=None)
assert reg._can_use_inplace_predict() is True
reg.set_params(booster="gblinear")
assert reg._can_use_inplace_predict() is False
def test_evaluation_metric():
from sklearn.datasets import load_diabetes, load_digits
from sklearn.metrics import mean_absolute_error
X, y = load_diabetes(return_X_y=True)
n_estimators = 16
with tm.captured_output() as (out, err):
reg = xgb.XGBRegressor(
tree_method="hist",
eval_metric=mean_absolute_error,
n_estimators=n_estimators,
)
reg.fit(X, y, eval_set=[(X, y)])
lines = out.getvalue().strip().split('\n')
assert len(lines) == n_estimators
for line in lines:
assert line.find("mean_absolute_error") != -1
def metric(predt: np.ndarray, Xy: xgb.DMatrix):
y = Xy.get_label()
return "m", np.abs(predt - y).sum()
with pytest.warns(UserWarning):
reg = xgb.XGBRegressor(
tree_method="hist",
n_estimators=1,
)
reg.fit(X, y, eval_set=[(X, y)], eval_metric=metric)
def merror(y_true: np.ndarray, predt: np.ndarray):
n_samples = y_true.shape[0]
assert n_samples == predt.size
errors = np.zeros(y_true.shape[0])
errors[y != predt] = 1.0
return np.sum(errors) / n_samples
X, y = load_digits(n_class=10, return_X_y=True)
clf = xgb.XGBClassifier(
tree_method="hist",
eval_metric=merror,
n_estimators=16,
objective="multi:softmax"
)
clf.fit(X, y, eval_set=[(X, y)])
custom = clf.evals_result()
clf = xgb.XGBClassifier(
tree_method="hist",
eval_metric="merror",
n_estimators=16,
objective="multi:softmax"
)
clf.fit(X, y, eval_set=[(X, y)])
internal = clf.evals_result()
np.testing.assert_allclose(
custom["validation_0"]["merror"],
internal["validation_0"]["merror"],
atol=1e-6
)
clf = xgb.XGBRFClassifier(
tree_method="hist", n_estimators=16,
objective=tm.softprob_obj(10),
eval_metric=merror,
)
with pytest.raises(AssertionError):
# shape check inside the `merror` function
clf.fit(X, y, eval_set=[(X, y)])