Python SCORERS.items方法代码示例

# 需要导入模块: from sklearn.metrics import SCORERS [as 别名]
# 或者: from sklearn.metrics.SCORERS import items [as 别名]
def test_scorer_sample_weight():
    # Test that scorers support sample_weight or raise sensible errors

    # Unlike the metrics invariance test, in the scorer case it's harder
    # to ensure that, on the classifier output, weighted and unweighted
    # scores really should be unequal.
    X, y = make_classification(random_state=0)
    _, y_ml = make_multilabel_classification(n_samples=X.shape[0], random_state=0)
    split = train_test_split(X, y, y_ml, random_state=0)
    X_train, X_test, y_train, y_test, y_ml_train, y_ml_test = split

    sample_weight = np.ones_like(y_test)
    sample_weight[:10] = 0

    # get sensible estimators for each metric
    sensible_regr = DummyRegressor(strategy="median")
    sensible_regr.fit(X_train, y_train)
    sensible_clf = DecisionTreeClassifier(random_state=0)
    sensible_clf.fit(X_train, y_train)
    sensible_ml_clf = DecisionTreeClassifier(random_state=0)
    sensible_ml_clf.fit(X_train, y_ml_train)
    estimator = dict(
        [(name, sensible_regr) for name in REGRESSION_SCORERS]
        + [(name, sensible_clf) for name in CLF_SCORERS]
        + [(name, sensible_ml_clf) for name in MULTILABEL_ONLY_SCORERS]
    )

    for name, scorer in SCORERS.items():
        if name in MULTILABEL_ONLY_SCORERS:
            target = y_ml_test
        else:
            target = y_test
        try:
            weighted = scorer(estimator[name], X_test, target, sample_weight=sample_weight)
            ignored = scorer(estimator[name], X_test[10:], target[10:])
            unweighted = scorer(estimator[name], X_test, target)
            assert_not_equal(
                weighted,
                unweighted,
                msg="scorer {0} behaves identically when "
                "called with sample weights: {1} vs "
                "{2}".format(name, weighted, unweighted),
            )
            assert_almost_equal(
                weighted,
                ignored,
                err_msg="scorer {0} behaves differently when "
                "ignoring samples and setting sample_weight to"
                " 0: {1} vs {2}".format(name, weighted, ignored),
            )

        except TypeError as e:
            assert_true(
                "sample_weight" in str(e),
                "scorer {0} raises unhelpful exception when called " "with sample weights: {1}".format(name, str(e)),
            )

# 需要导入模块: from sklearn.metrics import SCORERS [as 别名]
# 或者: from sklearn.metrics.SCORERS import items [as 别名]
def test_scorer_sample_weight():
    """Test that scorers support sample_weight or raise sensible errors"""

    # Unlike the metrics invariance test, in the scorer case it's harder
    # to ensure that, on the classifier output, weighted and unweighted
    # scores really should be unequal.
    X, y = make_classification(random_state=0)
    X_train, X_test, y_train, y_test = train_test_split(X, y, random_state=0)
    sample_weight = np.ones_like(y_test)
    sample_weight[:10] = 0

    # get sensible estimators for each metric
    sensible_regr = DummyRegressor(strategy='median')
    sensible_regr.fit(X_train, y_train)
    sensible_clf = DecisionTreeClassifier()
    sensible_clf.fit(X_train, y_train)
    estimator = dict([(name, sensible_regr)
                      for name in REGRESSION_SCORERS] +
                     [(name, sensible_clf)
                      for name in CLF_SCORERS])

    for name, scorer in SCORERS.items():
        try:
            weighted = scorer(estimator[name], X_test, y_test,
                              sample_weight=sample_weight)
            ignored = scorer(estimator[name], X_test[10:], y_test[10:])
            unweighted = scorer(estimator[name], X_test, y_test)
            assert_not_equal(weighted, unweighted,
                             "scorer {0} behaves identically when called with "
                             "sample weights: {1} vs {2}".format(name,
                                                                 weighted,
                                                                 unweighted))
            assert_equal(weighted, ignored,
                         "scorer {0} behaves differently when ignoring "
                         "samples and setting sample_weight to 0: "
                         "{1} vs {2}".format(name, weighted, ignored))

        except TypeError as e:
            assert_true("sample_weight" in str(e),
                        "scorer {0} raises unhelpful exception when called "
                        "with sample weights: {1}".format(name, str(e)))

# 需要导入模块: from sklearn.metrics import SCORERS [as 别名]
# 或者: from sklearn.metrics.SCORERS import items [as 别名]
def test_all_scorers_repr():
    # Test that all scorers have a working repr
    for name, scorer in SCORERS.items():
        repr(scorer)