/// <summary>チャネルごとの2次元カーネル積</summary>
        public static VariableNode ChannelwiseKernelProduct2D(VariableNode x, VariableNode y, int kwidth, int kheight, int stride)
        {
            Function function =
                new Functions.Connection2D.ChannelwiseKernelProduct(x.Shape, y.Shape, kwidth, kheight, stride);

            VariableNode w = Apply(function, x, y)[0];

            return(w);
        }
        /// <summary>チャネルごとの2次元カーネル積</summary>
        public static Tensor ChannelwiseKernelProduct2D(Tensor x, Tensor y, int kwidth, int kheight, int stride)
        {
            Functions.Connection2D.ChannelwiseKernelProduct function =
                new Functions.Connection2D.ChannelwiseKernelProduct(x.Shape, y.Shape, kwidth, kheight, stride);

            Tensor w = new Tensor(function.OutShape);

            function.Execute(new Tensor[] { x, y }, new Tensor[] { w });

            return(w);
        }