def test_number_of_subsets_of_features():
# In RFE, 'number_of_subsets_of_features'
# = the number of iterations in '_fit'
# = max(ranking_)
# = 1 + (n_features + step - n_features_to_select - 1) // step
# After optimization #4534, this number
# = 1 + np.ceil((n_features - n_features_to_select) / float(step))
# This test case is to test their equivalence, refer to #4534 and #3824
def formula1(n_features, n_features_to_select, step):
return 1 + ((n_features + step - n_features_to_select - 1) // step)
def formula2(n_features, n_features_to_select, step):
return 1 + np.ceil((n_features - n_features_to_select) / float(step))
# RFE
# Case 1, n_features - n_features_to_select is divisible by step
# Case 2, n_features - n_features_to_select is not divisible by step
n_features_list = [11, 11]
n_features_to_select_list = [3, 3]
step_list = [2, 3]
for n_features, n_features_to_select, step in zip(
n_features_list, n_features_to_select_list, step_list):
generator = check_random_state(43)
X = generator.normal(size=(100, n_features))
y = generator.rand(100).round()
rfe = RFE(estimator=SVC(kernel="linear"),
n_features_to_select=n_features_to_select,
step=step)
rfe.fit(X, y)
# this number also equals to the maximum of ranking_
assert (np.max(rfe.ranking_) == formula1(n_features,
n_features_to_select, step))
assert (np.max(rfe.ranking_) == formula2(n_features,
n_features_to_select, step))
# In RFECV, 'fit' calls 'RFE._fit'
# 'number_of_subsets_of_features' of RFE
# = the size of 'grid_scores' of RFECV
# = the number of iterations of the for loop before optimization #4534
# RFECV, n_features_to_select = 1
# Case 1, n_features - 1 is divisible by step
# Case 2, n_features - 1 is not divisible by step
n_features_to_select = 1
n_features_list = [11, 10]
step_list = [2, 2]
for n_features, step in zip(n_features_list, step_list):
generator = check_random_state(43)
X = generator.normal(size=(100, n_features))
y = generator.rand(100).round()
rfecv = RFECV(estimator=SVC(kernel="linear"), step=step)
rfecv.fit(X, y)
assert (rfecv.grid_scores_.shape[0] == formula1(
n_features, n_features_to_select, step))
assert (rfecv.grid_scores_.shape[0] == formula2(
n_features, n_features_to_select, step))
def test_make_rng():
# Check the check_random_state utility function behavior
assert check_random_state(None) is np.random.mtrand._rand
assert check_random_state(np.random) is np.random.mtrand._rand
rng_42 = np.random.RandomState(42)
assert check_random_state(42).randint(100) == rng_42.randint(100)
rng_42 = np.random.RandomState(42)
assert check_random_state(rng_42) is rng_42
rng_42 = np.random.RandomState(42)
assert check_random_state(43).randint(100) != rng_42.randint(100)
assert_raises(ValueError, check_random_state, "some invalid seed")
def test_kd_tree_query(metric, k, dualtree, breadth_first):
rng = check_random_state(0)
X = rng.random_sample((40, DIMENSION))
Y = rng.random_sample((10, DIMENSION))
kwargs = METRICS[metric]
check_neighbors(dualtree, breadth_first, k, metric, X, Y, kwargs)
def test_lda_dimension_warning(n_classes, n_features):
# FIXME: Future warning to be removed in 0.23
rng = check_random_state(0)
n_samples = 10
X = rng.randn(n_samples, n_features)
# we create n_classes labels by repeating and truncating a
# range(n_classes) until n_samples
y = np.tile(range(n_classes), n_samples // n_classes + 1)[:n_samples]
max_components = min(n_features, n_classes - 1)
for n_components in [max_components - 1, None, max_components]:
# if n_components <= min(n_classes - 1, n_features), no warning
lda = LinearDiscriminantAnalysis(n_components=n_components)
assert_no_warnings(lda.fit, X, y)
for n_components in [
max_components + 1,
max(n_features, n_classes - 1) + 1
]:
# if n_components > min(n_classes - 1, n_features), raise warning
# We test one unit higher than max_components, and then something
# larger than both n_features and n_classes - 1 to ensure the test
# works for any value of n_component
lda = LinearDiscriminantAnalysis(n_components=n_components)
msg = ("n_components cannot be larger than min(n_features, "
"n_classes - 1). Using min(n_features, "
"n_classes - 1) = min(%d, %d - 1) = %d components." %
(n_features, n_classes, max_components))
assert_warns_message(ChangedBehaviorWarning, msg, lda.fit, X, y)
future_msg = ("In version 0.23, setting n_components > min("
"n_features, n_classes - 1) will raise a "
"ValueError. You should set n_components to None"
" (default), or a value smaller or equal to "
"min(n_features, n_classes - 1).")
assert_warns_message(FutureWarning, future_msg, lda.fit, X, y)
def test_multinomial_loss():
# test if the multinomial loss and gradient computations are consistent
X, y = iris.data, iris.target.astype(np.float64)
n_samples, n_features = X.shape
n_classes = len(np.unique(y))
rng = check_random_state(42)
weights = rng.randn(n_features, n_classes)
intercept = rng.randn(n_classes)
sample_weights = rng.randn(n_samples)
np.abs(sample_weights, sample_weights)
# compute loss and gradient like in multinomial SAG
dataset, _ = make_dataset(X, y, sample_weights, random_state=42)
loss_1, grad_1 = _multinomial_grad_loss_all_samples(
dataset, weights, intercept, n_samples, n_features, n_classes)
# compute loss and gradient like in multinomial LogisticRegression
lbin = LabelBinarizer()
Y_bin = lbin.fit_transform(y)
weights_intercept = np.vstack((weights, intercept)).T.ravel()
loss_2, grad_2, _ = _multinomial_loss_grad(weights_intercept, X, Y_bin,
0.0, sample_weights)
grad_2 = grad_2.reshape(n_classes, -1)
grad_2 = grad_2[:, :-1].T
# comparison
assert_array_almost_equal(grad_1, grad_2)
assert_almost_equal(loss_1, loss_2)
def test_iforest_sparse():
"""Check IForest 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)
grid = ParameterGrid({"max_samples": [0.5, 1.0],
"bootstrap": [True, 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 grid:
# Trained on sparse format
sparse_classifier = IsolationForest(
n_estimators=10, random_state=1, **params).fit(X_train_sparse)
sparse_results = sparse_classifier.predict(X_test_sparse)
# Trained on dense format
dense_classifier = IsolationForest(
n_estimators=10, random_state=1, **params).fit(X_train)
dense_results = dense_classifier.predict(X_test)
assert_array_equal(sparse_results, dense_results)
def test_oneclass_decision_function():
# Test OneClassSVM decision function
clf = svm.OneClassSVM()
rnd = check_random_state(2)
# Generate train data
X = 0.3 * rnd.randn(100, 2)
X_train = np.r_[X + 2, X - 2]
# Generate some regular novel observations
X = 0.3 * rnd.randn(20, 2)
X_test = np.r_[X + 2, X - 2]
# Generate some abnormal novel observations
X_outliers = rnd.uniform(low=-4, high=4, size=(20, 2))
# fit the model
clf = svm.OneClassSVM(nu=0.1, kernel="rbf", gamma=0.1)
clf.fit(X_train)
# predict things
y_pred_test = clf.predict(X_test)
assert np.mean(y_pred_test == 1) > .9
y_pred_outliers = clf.predict(X_outliers)
assert np.mean(y_pred_outliers == -1) > .9
dec_func_test = clf.decision_function(X_test)
assert_array_equal((dec_func_test > 0).ravel(), y_pred_test == 1)
dec_func_outliers = clf.decision_function(X_outliers)
assert_array_equal((dec_func_outliers > 0).ravel(), y_pred_outliers == 1)
def test_rfe():
generator = check_random_state(0)
iris = load_iris()
X = np.c_[iris.data, generator.normal(size=(len(iris.data), 6))]
X_sparse = sparse.csr_matrix(X)
y = iris.target
# dense model
clf = SVC(kernel="linear")
rfe = RFE(estimator=clf, n_features_to_select=4, step=0.1)
rfe.fit(X, y)
X_r = rfe.transform(X)
clf.fit(X_r, y)
assert len(rfe.ranking_) == X.shape[1]
# sparse model
clf_sparse = SVC(kernel="linear")
rfe_sparse = RFE(estimator=clf_sparse, n_features_to_select=4, step=0.1)
rfe_sparse.fit(X_sparse, y)
X_r_sparse = rfe_sparse.transform(X_sparse)
assert X_r.shape == iris.data.shape
assert_array_almost_equal(X_r[:10], iris.data[:10])
assert_array_almost_equal(rfe.predict(X), clf.predict(iris.data))
assert rfe.score(X, y) == clf.score(iris.data, iris.target)
assert_array_almost_equal(X_r, X_r_sparse.toarray())
def test_compute_mi_cc():
# For two continuous variables a good approach is to test on bivariate
# normal distribution, where mutual information is known.
# Mean of the distribution, irrelevant for mutual information.
mean = np.zeros(2)
# Setup covariance matrix with correlation coeff. equal 0.5.
sigma_1 = 1
sigma_2 = 10
corr = 0.5
cov = np.array([[sigma_1**2, corr * sigma_1 * sigma_2],
[corr * sigma_1 * sigma_2, sigma_2**2]])
# True theoretical mutual information.
I_theory = (np.log(sigma_1) + np.log(sigma_2) -
0.5 * np.log(np.linalg.det(cov)))
rng = check_random_state(0)
Z = rng.multivariate_normal(mean, cov, size=1000)
x, y = Z[:, 0], Z[:, 1]
# Theory and computed values won't be very close, assert that the
# first figures after decimal point match.
for n_neighbors in [3, 5, 7]:
I_computed = _compute_mi(x, y, False, False, n_neighbors)
assert_almost_equal(I_computed, I_theory, 1)
def test_compute_mi_cd():
# To test define a joint distribution as follows:
# p(x, y) = p(x) p(y | x)
# X ~ Bernoulli(p)
# (Y | x = 0) ~ Uniform(-1, 1)
# (Y | x = 1) ~ Uniform(0, 2)
# Use the following formula for mutual information:
# I(X; Y) = H(Y) - H(Y | X)
# Two entropies can be computed by hand:
# H(Y) = -(1-p)/2 * ln((1-p)/2) - p/2*log(p/2) - 1/2*log(1/2)
# H(Y | X) = ln(2)
# Now we need to implement sampling from out distribution, which is
# done easily using conditional distribution logic.
n_samples = 1000
rng = check_random_state(0)
for p in [0.3, 0.5, 0.7]:
x = rng.uniform(size=n_samples) > p
y = np.empty(n_samples)
mask = x == 0
y[mask] = rng.uniform(-1, 1, size=np.sum(mask))
y[~mask] = rng.uniform(0, 2, size=np.sum(~mask))
I_theory = -0.5 * ((1 - p) * np.log(0.5 * (1 - p)) +
p * np.log(0.5 * p) + np.log(0.5)) - np.log(2)
# Assert the same tolerance.
for n_neighbors in [3, 5, 7]:
I_computed = _compute_mi(x, y, True, False, n_neighbors)
assert_almost_equal(I_computed, I_theory, 1)
def test_sample_weight_deviance():
# Test if deviance supports sample weights.
rng = check_random_state(13)
sample_weight = np.ones(100)
reg_y = rng.rand(100)
clf_y = rng.randint(0, 2, size=100)
mclf_y = rng.randint(0, 3, size=100)
for Loss in LOSS_FUNCTIONS.values():
if Loss is None:
continue
if issubclass(Loss, RegressionLossFunction):
k = 1
y = reg_y
p = reg_y
else:
k = 2
y = clf_y
p = clf_y
if Loss.is_multi_class:
k = 3
y = mclf_y
# one-hot encoding
p = np.zeros((y.shape[0], k), dtype=np.float64)
for i in range(k):
p[:, i] = y == i
loss = Loss(k)
deviance_w_w = loss(y, p, sample_weight)
deviance_wo_w = loss(y, p)
assert deviance_wo_w == deviance_w_w
def test_mutual_info_classif_mixed():
# Here the target is discrete and there are two continuous and one
# discrete feature. The idea of this test is clear from the code.
rng = check_random_state(0)
X = rng.rand(1000, 3)
X[:, 1] += X[:, 0]
y = ((0.5 * X[:, 0] + X[:, 2]) > 0.5).astype(int)
X[:, 2] = X[:, 2] > 0.5
mi = mutual_info_classif(X,
y,
discrete_features=[2],
n_neighbors=3,
random_state=0)
assert_array_equal(np.argsort(-mi), [2, 0, 1])
for n_neighbors in [5, 7, 9]:
mi_nn = mutual_info_classif(X,
y,
discrete_features=[2],
n_neighbors=n_neighbors,
random_state=0)
# Check that the continuous values have an higher MI with greater
# n_neighbors
assert mi_nn[0] > mi[0]
assert mi_nn[1] > mi[1]
# The n_neighbors should not have any effect on the discrete value
# The MI should be the same
assert mi_nn[2] == mi[2]
def test_ball_tree_pickle():
rng = check_random_state(0)
X = rng.random_sample((10, 3))
bt1 = BallTree(X, leaf_size=1)
# Test if BallTree with callable metric is picklable
bt1_pyfunc = BallTree(X, metric=dist_func, leaf_size=1, p=2)
ind1, dist1 = bt1.query(X)
ind1_pyfunc, dist1_pyfunc = bt1_pyfunc.query(X)
def check_pickle_protocol(protocol):
s = pickle.dumps(bt1, protocol=protocol)
bt2 = pickle.loads(s)
s_pyfunc = pickle.dumps(bt1_pyfunc, protocol=protocol)
bt2_pyfunc = pickle.loads(s_pyfunc)
ind2, dist2 = bt2.query(X)
ind2_pyfunc, dist2_pyfunc = bt2_pyfunc.query(X)
assert_array_almost_equal(ind1, ind2)
assert_array_almost_equal(dist1, dist2)
assert_array_almost_equal(ind1_pyfunc, ind2_pyfunc)
assert_array_almost_equal(dist1_pyfunc, dist2_pyfunc)
assert isinstance(bt2, BallTree)
for protocol in (0, 1, 2):
check_pickle_protocol(protocol)
def test_linearsvc_fit_sampleweight():
# check correct result when sample_weight is 1
n_samples = len(X)
unit_weight = np.ones(n_samples)
clf = svm.LinearSVC(random_state=0).fit(X, Y)
clf_unitweight = svm.LinearSVC(random_state=0).\
fit(X, Y, sample_weight=unit_weight)
# check if same as sample_weight=None
assert_array_equal(clf_unitweight.predict(T), clf.predict(T))
assert_allclose(clf.coef_, clf_unitweight.coef_, 1, 0.0001)
# check that fit(X) = fit([X1, X2, X3],sample_weight = [n1, n2, n3]) where
# X = X1 repeated n1 times, X2 repeated n2 times and so forth
random_state = check_random_state(0)
random_weight = random_state.randint(0, 10, n_samples)
lsvc_unflat = svm.LinearSVC(random_state=0).\
fit(X, Y, sample_weight=random_weight)
pred1 = lsvc_unflat.predict(T)
X_flat = np.repeat(X, random_weight, axis=0)
y_flat = np.repeat(Y, random_weight, axis=0)
lsvc_flat = svm.LinearSVC(random_state=0).fit(X_flat, y_flat)
pred2 = lsvc_flat.predict(T)
assert_array_equal(pred1, pred2)
assert_allclose(lsvc_unflat.coef_, lsvc_flat.coef_, 1, 0.0001)
def test_sample_weight_init_estimators():
# Smoke test for init estimators with sample weights.
rng = check_random_state(13)
X = rng.rand(100, 2)
sample_weight = np.ones(100)
reg_y = rng.rand(100)
clf_y = rng.randint(0, 2, size=100)
for Loss in LOSS_FUNCTIONS.values():
if Loss is None:
continue
if issubclass(Loss, RegressionLossFunction):
k = 1
y = reg_y
else:
k = 2
y = clf_y
if Loss.is_multi_class:
# skip multiclass
continue
loss = Loss(k)
init_est = loss.init_estimator()
init_est.fit(X, y)
out = loss.get_init_raw_predictions(X, init_est)
assert out.shape == (y.shape[0], 1)
sw_init_est = loss.init_estimator()
sw_init_est.fit(X, y, sample_weight=sample_weight)
sw_out = loss.get_init_raw_predictions(X, sw_init_est)
assert sw_out.shape == (y.shape[0], 1)
# check if predictions match
assert_allclose(out, sw_out, rtol=1e-2)
def test_iforest_subsampled_features():
# It tests non-regression for #5732 which failed at predict.
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)
clf = IsolationForest(max_features=0.8)
clf.fit(X_train, y_train)
clf.predict(X_test)
def test_query_haversine():
rng = check_random_state(0)
X = 2 * np.pi * rng.random_sample((40, 2))
bt = BallTree(X, leaf_size=1, metric='haversine')
dist1, ind1 = bt.query(X, k=5)
dist2, ind2 = brute_force_neighbors(X, X, k=5, metric='haversine')
assert_array_almost_equal(dist1, dist2)
assert_array_almost_equal(ind1, ind2)
def test_sample_weight_smoke():
rng = check_random_state(13)
y = rng.rand(100)
pred = rng.rand(100)
# least squares
loss = LeastSquaresError(1)
loss_wo_sw = loss(y, pred)
loss_w_sw = loss(y, pred, np.ones(pred.shape[0], dtype=np.float32))
assert_almost_equal(loss_wo_sw, loss_w_sw)
def generate_dataset(n_samples, centers, covariances, random_state=None):
"""Generate a multivariate normal data given some centers and
covariances"""
rng = check_random_state(random_state)
X = np.vstack([
rng.multivariate_normal(mean, cov, size=n_samples // len(centers))
for mean, cov in zip(centers, covariances)
])
y = np.hstack([[clazz] * (n_samples // len(centers))
for clazz in range(len(centers))])
return X, y
def test_safe_mask():
random_state = check_random_state(0)
X = random_state.rand(5, 4)
X_csr = sp.csr_matrix(X)
mask = [False, False, True, True, True]
mask = safe_mask(X, mask)
assert X[mask].shape[0] == 3
mask = safe_mask(X_csr, mask)
assert X_csr[mask].shape[0] == 3
def test_omp_reaches_least_squares():
# Use small simple data; it's a sanity check but OMP can stop early
rng = check_random_state(0)
n_samples, n_features = (10, 8)
n_targets = 3
X = rng.randn(n_samples, n_features)
Y = rng.randn(n_samples, n_targets)
omp = OrthogonalMatchingPursuit(n_nonzero_coefs=n_features)
lstsq = LinearRegression()
omp.fit(X, Y)
lstsq.fit(X, Y)
assert_array_almost_equal(omp.coef_, lstsq.coef_)
def test_rfecv_mockclassifier():
generator = check_random_state(0)
iris = load_iris()
X = np.c_[iris.data, generator.normal(size=(len(iris.data), 6))]
y = list(iris.target) # regression test: list should be supported
# Test using the score function
rfecv = RFECV(estimator=MockClassifier(), step=1)
rfecv.fit(X, y)
# non-regression test for missing worst feature:
assert len(rfecv.grid_scores_) == X.shape[1]
assert len(rfecv.ranking_) == X.shape[1]
def test_kd_tree_two_point(dualtree):
n_samples, n_features = (100, 3)
rng = check_random_state(0)
X = rng.random_sample((n_samples, n_features))
Y = rng.random_sample((n_samples, n_features))
r = np.linspace(0, 1, 10)
kdt = KDTree(X, leaf_size=10)
D = DistanceMetric.get_metric("euclidean").pairwise(Y, X)
counts_true = [(D <= ri).sum() for ri in r]
counts = kdt.two_point_correlation(Y, r=r, dualtree=dualtree)
assert_array_almost_equal(counts, counts_true)
def test_input_data_size():
# Regression test for #6288
# Previoulsly, a metric requiring a particular input dimension would fail
def custom_metric(x, y):
assert x.shape[0] == 3
return np.sum((x - y)**2)
rng = check_random_state(0)
X = rng.rand(10, 3)
pyfunc = DistanceMetric.get_metric("pyfunc", func=dist_func, p=2)
eucl = DistanceMetric.get_metric("euclidean")
assert_array_almost_equal(pyfunc.pairwise(X), eucl.pairwise(X))
def make_data(random_state, n_samples_per_center, grid_size, scale):
random_state = check_random_state(random_state)
centers = np.array([[i, j]
for i in range(grid_size)
for j in range(grid_size)])
n_clusters_true, n_features = centers.shape
noise = random_state.normal(
scale=scale, size=(n_samples_per_center, centers.shape[1]))
X = np.concatenate([c + noise for c in centers])
y = np.concatenate([[i] * n_samples_per_center
for i in range(n_clusters_true)])
return shuffle(X, y, random_state=random_state)
def test_linear_regression_sparse(random_state=0):
# Test that linear regression also works with sparse data
random_state = check_random_state(random_state)
for i in range(10):
n = 100
X = sparse.eye(n, n)
beta = random_state.rand(n)
y = X * beta[:, np.newaxis]
ols = LinearRegression()
ols.fit(X, y.ravel())
assert_array_almost_equal(beta, ols.coef_ + ols.intercept_)
assert_array_almost_equal(ols.predict(X) - y.ravel(), 0)
def test_rfe_mockclassifier():
generator = check_random_state(0)
iris = load_iris()
X = np.c_[iris.data, generator.normal(size=(len(iris.data), 6))]
y = iris.target
# dense model
clf = MockClassifier()
rfe = RFE(estimator=clf, n_features_to_select=4, step=0.1)
rfe.fit(X, y)
X_r = rfe.transform(X)
clf.fit(X_r, y)
assert len(rfe.ranking_) == X.shape[1]
assert X_r.shape == iris.data.shape
def test_kd_tree_kde(kernel, h):
n_samples, n_features = (100, 3)
rng = check_random_state(0)
X = rng.random_sample((n_samples, n_features))
Y = rng.random_sample((n_samples, n_features))
kdt = KDTree(X, leaf_size=10)
dens_true = compute_kernel_slow(Y, X, kernel, h)
for rtol in [0, 1E-5]:
for atol in [1E-6, 1E-2]:
for breadth_first in (True, False):
check_results(kernel, h, atol, rtol, breadth_first, Y, kdt,
dens_true)
def test_linear_regression_sparse_multiple_outcome(random_state=0):
# Test multiple-outcome linear regressions with sparse data
random_state = check_random_state(random_state)
X, y = make_sparse_uncorrelated(random_state=random_state)
X = sparse.coo_matrix(X)
Y = np.vstack((y, y)).T
n_features = X.shape[1]
ols = LinearRegression()
ols.fit(X, Y)
assert ols.coef_.shape == (2, n_features)
Y_pred = ols.predict(X)
ols.fit(X, y.ravel())
y_pred = ols.predict(X)
assert_array_almost_equal(np.vstack((y_pred, y_pred)).T, Y_pred, decimal=3)
def test_rfe_cv_groups():
generator = check_random_state(0)
iris = load_iris()
number_groups = 4
groups = np.floor(np.linspace(0, number_groups, len(iris.target)))
X = iris.data
y = (iris.target > 0).astype(int)
est_groups = RFECV(
estimator=RandomForestClassifier(random_state=generator),
step=1,
scoring='accuracy',
cv=GroupKFold(n_splits=2))
est_groups.fit(X, y, groups=groups)
assert est_groups.n_features_ > 0
