Traktor/myenv/Lib/site-packages/sklearn/tests/test_metaestimators.py
2024-05-23 01:57:24 +02:00

308 lines
10 KiB
Python

"""Common tests for metaestimators"""
import functools
from inspect import signature
import numpy as np
import pytest
from sklearn.base import BaseEstimator, is_regressor
from sklearn.datasets import make_classification
from sklearn.ensemble import BaggingClassifier
from sklearn.exceptions import NotFittedError
from sklearn.feature_extraction.text import TfidfVectorizer
from sklearn.feature_selection import RFE, RFECV
from sklearn.linear_model import LogisticRegression, Ridge
from sklearn.model_selection import GridSearchCV, RandomizedSearchCV
from sklearn.pipeline import Pipeline, make_pipeline
from sklearn.preprocessing import MaxAbsScaler, StandardScaler
from sklearn.semi_supervised import SelfTrainingClassifier
from sklearn.utils import all_estimators
from sklearn.utils._testing import set_random_state
from sklearn.utils.estimator_checks import (
_enforce_estimator_tags_X,
_enforce_estimator_tags_y,
)
from sklearn.utils.validation import check_is_fitted
class DelegatorData:
def __init__(
self,
name,
construct,
skip_methods=(),
fit_args=make_classification(random_state=0),
):
self.name = name
self.construct = construct
self.fit_args = fit_args
self.skip_methods = skip_methods
DELEGATING_METAESTIMATORS = [
DelegatorData("Pipeline", lambda est: Pipeline([("est", est)])),
DelegatorData(
"GridSearchCV",
lambda est: GridSearchCV(est, param_grid={"param": [5]}, cv=2),
skip_methods=["score"],
),
DelegatorData(
"RandomizedSearchCV",
lambda est: RandomizedSearchCV(
est, param_distributions={"param": [5]}, cv=2, n_iter=1
),
skip_methods=["score"],
),
DelegatorData("RFE", RFE, skip_methods=["transform", "inverse_transform"]),
DelegatorData("RFECV", RFECV, skip_methods=["transform", "inverse_transform"]),
DelegatorData(
"BaggingClassifier",
BaggingClassifier,
skip_methods=[
"transform",
"inverse_transform",
"score",
"predict_proba",
"predict_log_proba",
"predict",
],
),
DelegatorData(
"SelfTrainingClassifier",
lambda est: SelfTrainingClassifier(est),
skip_methods=["transform", "inverse_transform", "predict_proba"],
),
]
def test_metaestimator_delegation():
# Ensures specified metaestimators have methods iff subestimator does
def hides(method):
@property
def wrapper(obj):
if obj.hidden_method == method.__name__:
raise AttributeError("%r is hidden" % obj.hidden_method)
return functools.partial(method, obj)
return wrapper
class SubEstimator(BaseEstimator):
def __init__(self, param=1, hidden_method=None):
self.param = param
self.hidden_method = hidden_method
def fit(self, X, y=None, *args, **kwargs):
self.coef_ = np.arange(X.shape[1])
self.classes_ = []
return True
def _check_fit(self):
check_is_fitted(self)
@hides
def inverse_transform(self, X, *args, **kwargs):
self._check_fit()
return X
@hides
def transform(self, X, *args, **kwargs):
self._check_fit()
return X
@hides
def predict(self, X, *args, **kwargs):
self._check_fit()
return np.ones(X.shape[0])
@hides
def predict_proba(self, X, *args, **kwargs):
self._check_fit()
return np.ones(X.shape[0])
@hides
def predict_log_proba(self, X, *args, **kwargs):
self._check_fit()
return np.ones(X.shape[0])
@hides
def decision_function(self, X, *args, **kwargs):
self._check_fit()
return np.ones(X.shape[0])
@hides
def score(self, X, y, *args, **kwargs):
self._check_fit()
return 1.0
methods = [
k
for k in SubEstimator.__dict__.keys()
if not k.startswith("_") and not k.startswith("fit")
]
methods.sort()
for delegator_data in DELEGATING_METAESTIMATORS:
delegate = SubEstimator()
delegator = delegator_data.construct(delegate)
for method in methods:
if method in delegator_data.skip_methods:
continue
assert hasattr(delegate, method)
assert hasattr(
delegator, method
), "%s does not have method %r when its delegate does" % (
delegator_data.name,
method,
)
# delegation before fit raises a NotFittedError
if method == "score":
with pytest.raises(NotFittedError):
getattr(delegator, method)(
delegator_data.fit_args[0], delegator_data.fit_args[1]
)
else:
with pytest.raises(NotFittedError):
getattr(delegator, method)(delegator_data.fit_args[0])
delegator.fit(*delegator_data.fit_args)
for method in methods:
if method in delegator_data.skip_methods:
continue
# smoke test delegation
if method == "score":
getattr(delegator, method)(
delegator_data.fit_args[0], delegator_data.fit_args[1]
)
else:
getattr(delegator, method)(delegator_data.fit_args[0])
for method in methods:
if method in delegator_data.skip_methods:
continue
delegate = SubEstimator(hidden_method=method)
delegator = delegator_data.construct(delegate)
assert not hasattr(delegate, method)
assert not hasattr(
delegator, method
), "%s has method %r when its delegate does not" % (
delegator_data.name,
method,
)
def _generate_meta_estimator_instances_with_pipeline():
"""Generate instances of meta-estimators fed with a pipeline
Are considered meta-estimators all estimators accepting one of "estimator",
"base_estimator" or "estimators".
"""
for _, Estimator in sorted(all_estimators()):
sig = set(signature(Estimator).parameters)
if "estimator" in sig or "base_estimator" in sig or "regressor" in sig:
if is_regressor(Estimator):
estimator = make_pipeline(TfidfVectorizer(), Ridge())
param_grid = {"ridge__alpha": [0.1, 1.0]}
else:
estimator = make_pipeline(TfidfVectorizer(), LogisticRegression())
param_grid = {"logisticregression__C": [0.1, 1.0]}
if "param_grid" in sig or "param_distributions" in sig:
# SearchCV estimators
extra_params = {"n_iter": 2} if "n_iter" in sig else {}
yield Estimator(estimator, param_grid, **extra_params)
else:
yield Estimator(estimator)
elif "transformer_list" in sig:
# FeatureUnion
transformer_list = [
("trans1", make_pipeline(TfidfVectorizer(), MaxAbsScaler())),
(
"trans2",
make_pipeline(TfidfVectorizer(), StandardScaler(with_mean=False)),
),
]
yield Estimator(transformer_list)
elif "estimators" in sig:
# stacking, voting
if is_regressor(Estimator):
estimator = [
("est1", make_pipeline(TfidfVectorizer(), Ridge(alpha=0.1))),
("est2", make_pipeline(TfidfVectorizer(), Ridge(alpha=1))),
]
else:
estimator = [
(
"est1",
make_pipeline(TfidfVectorizer(), LogisticRegression(C=0.1)),
),
("est2", make_pipeline(TfidfVectorizer(), LogisticRegression(C=1))),
]
yield Estimator(estimator)
else:
continue
# TODO: remove data validation for the following estimators
# They should be able to work on any data and delegate data validation to
# their inner estimator(s).
DATA_VALIDATION_META_ESTIMATORS_TO_IGNORE = [
"AdaBoostClassifier",
"AdaBoostRegressor",
"BaggingClassifier",
"BaggingRegressor",
"ClassifierChain", # data validation is necessary
"IterativeImputer",
"OneVsOneClassifier", # input validation can't be avoided
"RANSACRegressor",
"RFE",
"RFECV",
"RegressorChain", # data validation is necessary
"SelfTrainingClassifier",
"SequentialFeatureSelector", # not applicable (2D data mandatory)
]
DATA_VALIDATION_META_ESTIMATORS = [
est
for est in _generate_meta_estimator_instances_with_pipeline()
if est.__class__.__name__ not in DATA_VALIDATION_META_ESTIMATORS_TO_IGNORE
]
def _get_meta_estimator_id(estimator):
return estimator.__class__.__name__
@pytest.mark.parametrize(
"estimator", DATA_VALIDATION_META_ESTIMATORS, ids=_get_meta_estimator_id
)
def test_meta_estimators_delegate_data_validation(estimator):
# Check that meta-estimators delegate data validation to the inner
# estimator(s).
rng = np.random.RandomState(0)
set_random_state(estimator)
n_samples = 30
X = rng.choice(np.array(["aa", "bb", "cc"], dtype=object), size=n_samples)
if is_regressor(estimator):
y = rng.normal(size=n_samples)
else:
y = rng.randint(3, size=n_samples)
# We convert to lists to make sure it works on array-like
X = _enforce_estimator_tags_X(estimator, X).tolist()
y = _enforce_estimator_tags_y(estimator, y).tolist()
# Calling fit should not raise any data validation exception since X is a
# valid input datastructure for the first step of the pipeline passed as
# base estimator to the meta estimator.
estimator.fit(X, y)
# n_features_in_ should not be defined since data is not tabular data.
assert not hasattr(estimator, "n_features_in_")