VAGSuite.ExcelInterface.AddData C# (CSharp) Method

        private double[,] AddData(int nRows, int nColumns, byte[] mapdata, bool isSixteenbit)
        {
            double[,] dataArray = new double[nRows, nColumns];
            double[] xarray = new double[nColumns];
            for (int i = 0; i < xarray.Length; i++)
            {
                xarray[i] = -3.0f + i * 0.25f;
            }
            double[] yarray = xarray;

            int mapindex = 0;
            for (int i = 0; i < dataArray.GetLength(0); i++)
            {
                for (int j = 0; j < dataArray.GetLength(1); j++)
                {
                    if (isSixteenbit)
                    {
                        byte val1 = (byte)mapdata.GetValue(mapindex++);
                        byte val2 = (byte)mapdata.GetValue(mapindex++);
                        bool convertSign = false;
                        if (val1 == 0xff)
                        {
                            val1 = 0;
                            val2 = (byte)(0x100 - val2);
                            convertSign = true;
                        }
                        int ival1 = Convert.ToInt32(val1);
                        int ival2 = Convert.ToInt32(val2);
                        double value = (ival1 * 256) + ival2;
                        if (convertSign) value = -value;
                        dataArray[i, j] = value;
                    }
                    else
                    {
                        byte val1 = (byte)mapdata.GetValue(mapindex++);
                        int ival1 = Convert.ToInt32(val1);

                        double value = ival1;
                        dataArray[i, j] = value;
                    }
                }
            }
            return dataArray;
        }