Accord.Tests.Math.MatrixTest.SolveTest1 C# (CSharp) Method

        public void SolveTest1()
        {
            double[,] a = 
            {
                { 1, 2, 3 },
                { 4, 5, 6 },
            };

            double[,] b = 
            {
                {  7,  8,  9 },
                { 10, 11, 12 },
            };

            // Test with more rows than columns
            {
                double[,] matrix = a.Transpose();
                double[,] rightSide = b.Transpose();

                Assert.IsTrue(matrix.GetLength(0) > matrix.GetLength(1));

                double[,] expected = 
                {
                    { -1, -2 },
                    {  2,  3 }
                };


                double[,] actual = Matrix.Solve(matrix, rightSide);

                Assert.IsTrue(expected.IsEqual(actual, 1e-10));
            }

            // test with more columns than rows
            {
                double[,] matrix = a;
                double[,] rightSide = b;

                Assert.IsTrue(matrix.GetLength(0) < matrix.GetLength(1));


                double[,] expected = 
                {
                    { -13/6.0,  -8/3.0, -19/6.0 },
                    {   2/6.0,   2/6.0,   2/6.0 },
                    {  17/6.0,  20/6.0,  23/6.0 }
                };

                double[,] actual = Matrix.Solve(matrix, rightSide);

                Assert.IsTrue(expected.IsEqual(actual, 1e-10));
            }
        }