Accord.Tests.Math.QrDecompositionTest.SolveTest2 C# (CSharp) Method

        public void SolveTest2()
        {
            // Example from Lecture notes for MATHS 370: Advanced Numerical Methods
            // http://www.math.auckland.ac.nz/~sharp/370/qr-solving.pdf

            double[,] value =
            {
                { 1,           0,           0 },
                { 1,           7,          49 },
                { 1,          14,         196 },
                { 1,          21,         441 },
                { 1,          28,         784 },
                { 1,          35,        1225 },
            };

            // Matrices
            {
                double[,] b = 
                {
                    { 4 },
                    { 1 },
                    { 0 },
                    { 0 }, 
                    { 2 },
                    { 5 },
                };

                double[,] expected =
                {
                    { 3.9286  },
                    { -0.5031 },
                    { 0.0153  },
                };

                var target = new QrDecomposition(value);
                double[,] actual = target.Solve(b);

                Assert.IsTrue(Matrix.IsEqual(expected, actual, atol: 1e-4));
                Assert.IsTrue(Matrix.IsEqual(value, target.Reverse(), 1e-6));


                var target2 = new JaggedQrDecomposition(value.ToJagged());
                double[][] actual2 = target2.Solve(b.ToJagged());

                Assert.IsTrue(Matrix.IsEqual(expected, actual2, atol: 1e-4));
                Assert.IsTrue(Matrix.IsEqual(value, target2.Reverse(), 1e-6));
            }

            // Vectors
            {
                double[] b = { 4, 1, 0, 0, 2, 5 };
                double[] expected = { 3.9286, -0.5031, 0.0153 };

                var target = new QrDecomposition(value);
                double[] actual = target.Solve(b);

                Assert.IsTrue(Matrix.IsEqual(expected, actual, atol: 1e-4));
            }
        }