def test_ovr_partial_fit_exceptions():
ovr = OneVsRestClassifier(MultinomialNB())
X = np.abs(np.random.randn(14, 2))
y = [1, 1, 1, 1, 2, 3, 3, 0, 0, 2, 3, 1, 2, 3]
ovr.partial_fit(X[:7], y[:7], np.unique(y))
# A new class value which was not in the first call of partial_fit
# It should raise ValueError
y1 = [5] + y[7:-1]
assert_raises_regexp(ValueError, r"Mini-batch contains \[.+\] while "
r"classes must be subset of \[.+\]",
ovr.partial_fit,
X=X[7:],
y=y1)
def test_ovr_partial_fit():
# Test if partial_fit is working as intended
X, y = shuffle(iris.data, iris.target, random_state=0)
ovr = OneVsRestClassifier(MultinomialNB())
ovr.partial_fit(X[:100], y[:100], np.unique(y))
ovr.partial_fit(X[100:], y[100:])
pred = ovr.predict(X)
ovr2 = OneVsRestClassifier(MultinomialNB())
pred2 = ovr2.fit(X, y).predict(X)
assert_almost_equal(pred, pred2)
assert len(ovr.estimators_) == len(np.unique(y))
assert np.mean(y == pred) > 0.65
# Test when mini batches doesn't have all classes
# with SGDClassifier
X = np.abs(np.random.randn(14, 2))
y = [1, 1, 1, 1, 2, 3, 3, 0, 0, 2, 3, 1, 2, 3]
ovr = OneVsRestClassifier(
SGDClassifier(max_iter=1, tol=None, shuffle=False, random_state=0))
ovr.partial_fit(X[:7], y[:7], np.unique(y))
ovr.partial_fit(X[7:], y[7:])
pred = ovr.predict(X)
ovr1 = OneVsRestClassifier(
SGDClassifier(max_iter=1, tol=None, shuffle=False, random_state=0))
pred1 = ovr1.fit(X, y).predict(X)
assert np.mean(pred == y) == np.mean(pred1 == y)
# test partial_fit only exists if estimator has it:
ovr = OneVsRestClassifier(SVC())
assert not hasattr(ovr, "partial_fit")