def test_gnb_pfit_wrong_nb_features():
 clf = GaussianNB()
 clf.fit(X, y)
 assert_raises(ValueError, clf.partial_fit, np.hstack((X, X)), y)

def test_gnb_pfit_wrong_nb_features ( ) : clf = GaussianNB ( ) clf . fit ( X , y ) assert_raises ( ValueError , clf . partial_fit , np . hstack ( ( X , X ) ) , y )
test whether an error is raised when the number of feature changes between two partial fit .