Accord.Tests.Math.CDF97Test.FWT97Test C# (CSharp) Method

        public void FWT97Test()
        {
            double[] x = new double[32];

            // Makes a fancy cubic signal
            for (int i = 0; i < 32; i++)
                x[i] = 5 + i + 0.4 * i * i - 0.02 * i * i * i;

            double[] original = 
            {
                5.000000,    6.380000,    8.440000,   11.060000,
                14.120000,   17.500000,   21.080000,  24.740000,
                28.360000,   31.820000,   35.000000,  37.780000,
                40.040000,   41.660000,   42.520000,  42.500000,
                41.480000,   39.340000,   35.960000,  31.220000,
                25.000000,   17.180000,   7.640000,   -3.740000, 
               -17.080000,  -32.500000,  -50.120000,  -70.060000, 
               -92.440000, -117.380000, -145.000000, -175.420000 
            };

            double[] wc =
            {
                 7.752539,   12.210715,   20.072860,   29.837663,
                40.055014,   49.367269,   56.416781,   59.845907,
                58.297001,   50.412419,   34.834515,   10.205643,
               -24.831840, -71.635579,  -129.151279, -208.800687,
                 0.157752,   0.000000,     0.000000,    0.000000,
                 0.000000,   0.000000,     0.000000,    0.000000,
                 0.000000,   0.000000,     0.000000,   -0.000000,
                -0.000000,  -0.000000,     4.114999,  -19.449089
            };

            Assert.IsTrue(Matrix.IsEqual(x, original, 0.0001));

            // Do the forward 9/7 transform
            CDF97.FWT97(x);

            Assert.IsTrue(Matrix.IsEqual(x, wc, 0.0001));

            // Do the inverse 9/7 transform
            CDF97.IWT97(x);

            Assert.IsTrue(Matrix.IsEqual(x, original, 0.0001));

        }