xgboost/tests/python/test_early_stopping.py
Oleksandr Pryimak 986fee6022 pytest tests/python fails if no pandas installed (#4620)
* _maybe_pandas_xxx should return their arguments unchanged if no pandas installed

* Tests should not assume pandas is installed

* Mark tests which require pandas as such
2019-07-01 02:54:08 +08:00

83 lines
3.1 KiB
Python

import xgboost as xgb
import testing as tm
import numpy as np
import unittest
import pytest
rng = np.random.RandomState(1994)
class TestEarlyStopping(unittest.TestCase):
@pytest.mark.skipif(**tm.no_sklearn())
def test_early_stopping_nonparallel(self):
from sklearn.datasets import load_digits
try:
from sklearn.model_selection import train_test_split
except ImportError:
from sklearn.cross_validation import train_test_split
digits = load_digits(2)
X = digits['data']
y = digits['target']
X_train, X_test, y_train, y_test = train_test_split(X, y,
random_state=0)
clf1 = xgb.XGBClassifier()
clf1.fit(X_train, y_train, early_stopping_rounds=5, eval_metric="auc",
eval_set=[(X_test, y_test)])
clf2 = xgb.XGBClassifier()
clf2.fit(X_train, y_train, early_stopping_rounds=4, eval_metric="auc",
eval_set=[(X_test, y_test)])
# should be the same
assert clf1.best_score == clf2.best_score
assert clf1.best_score != 1
# check overfit
clf3 = xgb.XGBClassifier()
clf3.fit(X_train, y_train, early_stopping_rounds=10, eval_metric="auc",
eval_set=[(X_test, y_test)])
assert clf3.best_score == 1
@pytest.mark.skipif(**tm.no_sklearn())
def evalerror(self, preds, dtrain):
from sklearn.metrics import mean_squared_error
labels = dtrain.get_label()
return 'rmse', mean_squared_error(labels, preds)
@staticmethod
def assert_metrics_length(cv, expected_length):
for key, value in cv.items():
assert len(value) == expected_length
@pytest.mark.skipif(**tm.no_sklearn())
def test_cv_early_stopping(self):
from sklearn.datasets import load_digits
digits = load_digits(2)
X = digits['data']
y = digits['target']
dm = xgb.DMatrix(X, label=y)
params = {'max_depth': 2, 'eta': 1, 'verbosity': 0,
'objective': 'binary:logistic'}
cv = xgb.cv(params, dm, num_boost_round=10, nfold=10,
early_stopping_rounds=10)
self.assert_metrics_length(cv, 10)
cv = xgb.cv(params, dm, num_boost_round=10, nfold=10,
early_stopping_rounds=5)
self.assert_metrics_length(cv, 3)
cv = xgb.cv(params, dm, num_boost_round=10, nfold=10,
early_stopping_rounds=1)
self.assert_metrics_length(cv, 1)
cv = xgb.cv(params, dm, num_boost_round=10, nfold=10,
feval=self.evalerror, early_stopping_rounds=10)
self.assert_metrics_length(cv, 10)
cv = xgb.cv(params, dm, num_boost_round=10, nfold=10,
feval=self.evalerror, early_stopping_rounds=1)
self.assert_metrics_length(cv, 5)
cv = xgb.cv(params, dm, num_boost_round=10, nfold=10,
feval=self.evalerror, maximize=True,
early_stopping_rounds=1)
self.assert_metrics_length(cv, 1)