public void OverflowTest()
        {
            foreach (bool transpose in new bool[] { false, true })
            {
                foreach (int batch in new int[] { 1, 2, 3 })
                {
                    foreach (int inchannels in new int[] { 4, 8, 12 })
                    {
                        foreach (int outchannels in new int[] { 4, 8, 12 })
                        {
                            float[] xval = (new float[inchannels * batch]).Select((_, idx) => idx * 1e-3f).ToArray();
                            float[] yval = (new float[outchannels * batch]).Select((_, idx) => idx * 1e-3f).Reverse().ToArray();

                            OverflowCheckedTensor x_tensor = new OverflowCheckedTensor(Shape.Map0D(inchannels, batch), xval);
                            OverflowCheckedTensor y_tensor = new OverflowCheckedTensor(Shape.Map0D(outchannels, batch), yval);

                            OverflowCheckedTensor gw_tensor = new OverflowCheckedTensor(Shape.Kernel0D(inchannels, outchannels / 4));

                            QuaternionKernelProductDense ope = new QuaternionKernelProductDense(inchannels, outchannels, transpose, batch);

                            ope.Execute(x_tensor, y_tensor, gw_tensor);

                            CollectionAssert.AreEqual(xval, x_tensor.State);
                            CollectionAssert.AreEqual(yval, y_tensor.State);

                            gw_tensor.CheckOverflow();

                            Console.WriteLine($"pass: {inchannels},{outchannels},{batch},{transpose}");
                        }
                    }
                }
            }
        }
        public void ExecuteTest()
        {
            float max_err = 0;

            foreach (int batch in new int[] { 1, 2, 3 })
            {
                foreach (int inchannels in new int[] { 4, 8, 12 })
                {
                    foreach (int outchannels in new int[] { 4, 8, 12 })
                    {
                        float[] xval = (new float[inchannels * batch]).Select((_, idx) => idx * 1e-3f).ToArray();
                        float[] yval = (new float[outchannels * batch]).Select((_, idx) => idx * 1e-3f).Reverse().ToArray();

                        Quaternion[] xcval = (new Quaternion[xval.Length / 4])
                                             .Select((_, idx) => new Quaternion(xval[idx * 4], xval[idx * 4 + 1], xval[idx * 4 + 2], xval[idx * 4 + 3])).ToArray();

                        Quaternion[] ycval = (new Quaternion[yval.Length / 4])
                                             .Select((_, idx) => new Quaternion(yval[idx * 4], yval[idx * 4 + 1], yval[idx * 4 + 2], yval[idx * 4 + 3])).ToArray();

                        QuaternionMap0D x = new QuaternionMap0D(inchannels / 4, batch, xcval);
                        QuaternionMap0D y = new QuaternionMap0D(outchannels / 4, batch, ycval);

                        QuaternionFilter0D gw = Reference(x, y);

                        OverflowCheckedTensor x_tensor = new OverflowCheckedTensor(Shape.Map0D(inchannels, batch), xval);
                        OverflowCheckedTensor y_tensor = new OverflowCheckedTensor(Shape.Map0D(outchannels, batch), yval);

                        OverflowCheckedTensor gw_tensor = new OverflowCheckedTensor(Shape.Kernel0D(inchannels, outchannels / 4));

                        QuaternionKernelProductDense ope = new QuaternionKernelProductDense(inchannels, outchannels, transpose: false, batch);

                        ope.Execute(x_tensor, y_tensor, gw_tensor);

                        float[] gw_expect = gw.ToArray();
                        float[] gw_actual = gw_tensor.State;

                        CollectionAssert.AreEqual(xval, x_tensor.State);
                        CollectionAssert.AreEqual(yval, y_tensor.State);

                        AssertError.Tolerance(gw_expect, gw_actual, 1e-7f, 1e-5f, ref max_err, $"mismatch value {inchannels},{outchannels},{batch}");

                        Console.WriteLine($"pass: {inchannels},{outchannels},{batch}");
                    }
                }
            }

            Console.WriteLine($"maxerr:{max_err}");
        }
        public void SpeedTest()
        {
            int inchannels = 32, outchannels = 32;

            OverflowCheckedTensor x_tensor   = new OverflowCheckedTensor(Shape.Map0D(inchannels));
            OverflowCheckedTensor y_tensor   = new OverflowCheckedTensor(Shape.Map0D(outchannels));

            OverflowCheckedTensor gw_tensor  = new OverflowCheckedTensor(Shape.Kernel0D(inchannels, outchannels / 4));

            QuaternionKernelProductDense ope = new QuaternionKernelProductDense(inchannels, outchannels);

            Stopwatch sw = new Stopwatch();

            sw.Start();

            ope.Execute(x_tensor, y_tensor, gw_tensor);
            ope.Execute(x_tensor, y_tensor, gw_tensor);
            ope.Execute(x_tensor, y_tensor, gw_tensor);
            ope.Execute(x_tensor, y_tensor, gw_tensor);

            sw.Stop();

            Console.WriteLine($"{sw.ElapsedMilliseconds / 4} msec");
        }