public void testQuinticMin() throws MathException {
// The quintic function has zeros at 0, +-0.5 and +-1.
// The function has extrema (first derivative is zero) at 0.27195613 and 0.82221643,
UnivariateRealFunction f = new QuinticFunction();
UnivariateRealOptimizer minimizer = new BrentOptimizer();
assertEquals(-0.27195613, minimizer.optimize(f, GoalType.MINIMIZE, -0.3, -0.2), 1.0e-8);
assertEquals( 0.82221643, minimizer.optimize(f, GoalType.MINIMIZE, 0.3, 0.9), 1.0e-8);
assertTrue(minimizer.getIterationCount() <= 50);
// search in a large interval
assertEquals(-0.27195613, minimizer.optimize(f, GoalType.MINIMIZE, -1.0, 0.2), 1.0e-8);