private void Form1_Load(object sender, EventArgs e)
        {
            double[] inp = new double[] { -36, 33, -10, 1, 17, -32, 1, -3, 5 };

            mainChart.Series.Clear();
            mainChart.Series.Add("Frequencies");


            Func <double, double> foo  = PolynomialFactory.getPolynomialFunction(inp);
            Func <double, double> fooD = PolynomialFactory.getPolynomialDerivative(inp);

            ImprovedNewtonRaphsonMethodD rootFinder = new ImprovedNewtonRaphsonMethodD(foo, fooD);
            double x1 = float.MinValue, x2 = 1.84;
            double equalsTo = 0;

            rootFinder.ExpandBracket(ref x1, ref x2, equalsTo);

            double root = rootFinder.FindRoot(x1, x2, equalsTo);

            MessageBox.Show("Root is: " + root + "    x1: " + x1 + ";   x2: " + x2);
        }
        public void FindRootTest1()
        {
            Func <double, double> polynomial        = x => (x - 1) * (x - 10) * (x - 18);
            Func <double, double> computeDerivative = x => 3 * x * x - 58 * x + 208;

            ImprovedNewtonRaphsonMethodD rootFinder = new ImprovedNewtonRaphsonMethodD(polynomial, computeDerivative);

            rootFinder.EpsilonX = Numeric.EpsilonD / 100;

            double xRoot = rootFinder.FindRoot(0, 2);

            Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
            Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

            xRoot = rootFinder.FindRoot(4, 10);
            Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
            Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

            xRoot = rootFinder.FindRoot(10, 4);
            Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
            Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

            xRoot = rootFinder.FindRoot(10, 12);
            Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
            Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

            xRoot = rootFinder.FindRoot(2, 0);
            Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
            Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

            xRoot = rootFinder.FindRoot(0, 3);
            Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
            Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

            xRoot = rootFinder.FindRoot(3, 0);
            Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
            Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

            xRoot = rootFinder.FindRoot(-6, 2);
            Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
            Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

            xRoot = rootFinder.FindRoot(-1, 1);
            Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
            Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

            xRoot = rootFinder.FindRoot(-1, 1);
            Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
            Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

            xRoot = rootFinder.FindRoot(0.9, 9.9);
            Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
            Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

            xRoot = rootFinder.FindRoot(2, 3);
            Assert.IsTrue(double.IsNaN(xRoot));
            Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

            xRoot = rootFinder.FindRoot(3, 2);
            Assert.IsTrue(double.IsNaN(xRoot));
            Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

            rootFinder.MaxNumberOfIterations = 1;
            xRoot = rootFinder.FindRoot(0, 1000);
            Assert.IsTrue(double.IsNaN(xRoot));
            Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);
        }
        public void FindRootTest1()
        {
            Func<double, double> polynomial = x => (x - 1)*(x - 10)*(x - 18);
              Func<double, double> computeDerivative = x => 3 * x * x - 58 * x + 208;

              ImprovedNewtonRaphsonMethodD rootFinder = new ImprovedNewtonRaphsonMethodD(polynomial, computeDerivative);

              rootFinder.EpsilonX = Numeric.EpsilonD / 100;

              double xRoot = rootFinder.FindRoot(0, 2);
              Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
              Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

              xRoot = rootFinder.FindRoot(4, 10);
              Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
              Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

              xRoot = rootFinder.FindRoot(10, 4);
              Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
              Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

              xRoot = rootFinder.FindRoot(10, 12);
              Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
              Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

              xRoot = rootFinder.FindRoot(2, 0);
              Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
              Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

              xRoot = rootFinder.FindRoot(0, 3);
              Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
              Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

              xRoot = rootFinder.FindRoot(3, 0);
              Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
              Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

              xRoot = rootFinder.FindRoot(-6, 2);
              Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
              Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

              xRoot = rootFinder.FindRoot(-1, 1);
              Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
              Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

              xRoot = rootFinder.FindRoot(-1, 1);
              Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
              Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

              xRoot = rootFinder.FindRoot(0.9, 9.9);
              Assert.IsTrue(Numeric.AreEqual(0, polynomial(xRoot)));
              Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

              xRoot = rootFinder.FindRoot(2, 3);
              Assert.IsTrue(double.IsNaN(xRoot));
              Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

              xRoot = rootFinder.FindRoot(3, 2);
              Assert.IsTrue(double.IsNaN(xRoot));
              Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);

              rootFinder.MaxNumberOfIterations = 1;
              xRoot = rootFinder.FindRoot(0, 1000);
              Assert.IsTrue(double.IsNaN(xRoot));
              Console.WriteLine("NumberOfIterations: {0}", rootFinder.NumberOfIterations);
        }