public void test1dLinearRegression()
        {
            //BOOST_MESSAGE("Testing 1d simple linear least-squares regression...");

            /* Example taken from the QuantLib-User list, see posting
             * Multiple linear regression/weighted regression, Boris Skorodumov */

            //SavedSettings backup;

            List <double> x = new InitializedList <double>(9),
                          y = new InitializedList <double>(9);

            x[0] = 2.4; x[1] = 1.8; x[2] = 2.5; x[3] = 3.0;
            x[4] = 2.1; x[5] = 1.2; x[6] = 2.0; x[7] = 2.7; x[8] = 3.6;

            y[0] = 7.8; y[1] = 5.5; y[2] = 8.0; y[3] = 9.0;
            y[4] = 6.5; y[5] = 4.0; y[6] = 6.3; y[7] = 8.4; y[8] = 10.2;

            List <Func <double, double> > v = new List <Func <double, double> >();

            v.Add(a => 1.0);
            v.Add(a => a);

            LinearRegression m = new LinearRegression(x, y);

            const double tol = 0.0002;

            double[] coeffExpected  = new double[] { 0.9448, 2.6853 };
            double[] errorsExpected = new double[] { 0.3654, 0.1487 };

            for (int i = 0; i < 2; ++i)
            {
                if (Math.Abs(m.standardErrors()[i] - errorsExpected[i]) > tol)
                {
                    Assert.Fail("Failed to reproduce linear regression standard errors"
                                + "\n    calculated: " + m.standardErrors()[i]
                                + "\n    expected:   " + errorsExpected[i]
                                + "\n    tolerance:  " + tol);
                }

                if (Math.Abs(m.coefficients()[i] - coeffExpected[i]) > tol)
                {
                    Assert.Fail("Failed to reproduce linear regression coef."
                                + "\n    calculated: " + m.coefficients()[i]
                                + "\n    expected:   " + coeffExpected[i]
                                + "\n    tolerance:  " + tol);
                }
            }
        }
        public void test1dLinearRegression()
        {
            //BOOST_MESSAGE("Testing 1d simple linear least-squares regression...");

            /* Example taken from the QuantLib-User list, see posting
             * Multiple linear regression/weighted regression, Boris Skorodumov */

            //SavedSettings backup;

            List<double> x = new InitializedList<double>(9),
                         y = new InitializedList<double>(9);
            x[0] = 2.4; x[1] = 1.8; x[2] = 2.5; x[3] = 3.0;
            x[4] = 2.1; x[5] = 1.2; x[6] = 2.0; x[7] = 2.7; x[8] = 3.6;

            y[0] = 7.8; y[1] = 5.5; y[2] = 8.0; y[3] = 9.0;
            y[4] = 6.5; y[5] = 4.0; y[6] = 6.3; y[7] = 8.4; y[8] = 10.2;

            List<Func<double, double>> v = new List<Func<double, double>>();
            v.Add(a => 1.0);
            v.Add(a => a);

            LinearRegression m = new LinearRegression(x, y);

            const double tol = 0.0002;
            double[] coeffExpected = new double[] { 0.9448, 2.6853 };
            double[] errorsExpected = new double[] { 0.3654, 0.1487 };

            for (int i = 0; i < 2; ++i) {
                if (Math.Abs(m.standardErrors()[i] - errorsExpected[i]) > tol) {
                    Assert.Fail("Failed to reproduce linear regression standard errors"
                                + "\n    calculated: " + m.standardErrors()[i]
                                + "\n    expected:   " + errorsExpected[i]
                                + "\n    tolerance:  " + tol);
                }

                if (Math.Abs(m.coefficients()[i] - coeffExpected[i]) > tol) {
                    Assert.Fail("Failed to reproduce linear regression coef."
                                + "\n    calculated: " + m.coefficients()[i]
                                + "\n    expected:   " + coeffExpected[i]
                                + "\n    tolerance:  " + tol);
                }
            }
        }