@Test
public void testRealOnlyCubic() {
Double[] result = REAL_ONLY_CUBIC.getRoots(ONE_REAL_ROOT);
assertEquals(result.length, 1);
assertEquals(result[0], 1, 0);
result = REAL_ONLY_CUBIC.getRoots(ONE_DISTINCT_ROOT);
assertEquals(result.length, 3);
for (final Double d : result) {
assertEquals(d, 1, EPS);
}
result = REAL_ONLY_CUBIC.getRoots(THREE_ROOTS);
assertEquals(result.length, 3);
assertEquals(result[0], 1, EPS);
assertEquals(result[1], 3, EPS);
assertEquals(result[2], 2, EPS);
}
@Test(expectedExceptions = IllegalArgumentException.class)
public void testNonCubic2() {
REAL_ONLY_CUBIC.getRoots(new RealPolynomialFunction1D(new double[] {1, 1, 1, 1, 1}));
}
@Test(expectedExceptions = IllegalArgumentException.class)
public void testNullFunction2() {
REAL_ONLY_CUBIC.getRoots(null);
}