def test_list_feature_union_drops(X):
"""Check the the drop of ``ListFeatureUnion`` keeps the correct
number of samples"""
drop_0_1 = ListFeatureUnion([('drop' + str(k), 'drop') for k in range(2)])
x_01_a = drop_0_1.fit_transform(X)
x_01_b = drop_0_1.transform(X)
assert x_01_a.shape == (X.shape[0], 0)
assert x_01_b.shape == (X.shape[0], 0)
def test_list_feature_union_transform(X):
"""Check that a ``ListFeatureUnion`` of two projections gives the same
result as stacking the projections."""
list_dim = [0, 1]
p_1_2 = ListFeatureUnion([("proj" + str(k), Projection(columns=k))
for k in list_dim])
p12 = Projection(columns=list_dim)
for p in [p12, p_1_2]:
p.fit(X)
x_12 = p12.transform(X)
x_1_2 = np.concatenate(p_1_2.transform(X), axis=1)
assert_almost_equal(x_12, x_1_2)