//update method from the observer, to update datagrid with realtimedata
        public void Update(Class_RealTimeData subject)
        {
            dataGridView1.Rows.Clear();

            //workout max possible length using buyordersize and sellordersize
            int size;

            if (currCompany.getSellOrderSize() > currCompany.getBuyOrderSize())
            {
                size = currCompany.getSellOrderSize();
            }
            else
            {
                size = currCompany.getBuyOrderSize();
            }

            //for loop to add data to each row of the datagrid
            for (int i = 0; i < size; i++)
            {
                //if a row contains seller order only ie: more sellers than buyers so first 2 rows are blank at some point
                if (i >= currCompany.getBuyOrderSize())
                {
                    dataGridView1.Rows.Add("", "", currCompany.getSellOrder(i).getPrice(), currCompany.getSellOrder(i).getOrderSize());
                }

                //if a row contains buyer order only ie: more buyers than selles so first 2 rows are blank at some point
                else if (i >= currCompany.getSellOrderSize())
                {
                    dataGridView1.Rows.Add(currCompany.getBuyOrder(i).getOrderSize(), currCompany.getBuyOrder(i).getPrice());
                }

                //else called on rows that contain both buyers and sellers
                else
                {
                    dataGridView1.Rows.Add(currCompany.getBuyOrder(i).getOrderSize(), currCompany.getBuyOrder(i).getPrice(), currCompany.getSellOrder(i).getPrice(), currCompany.getSellOrder(i).getOrderSize());
                }

                //limit of the top 10 so break out of the for loop
                if (i == 9)
                {
                    break;
                }
            }
        }
        //update method from the observer, to update datagrid with realtimedata
        public void Update(Class_RealTimeData subject)
        {
            dataGridView1.Rows.Clear();

            //create a temporary set of buy and sell orders
            //group each by price, to join orders with the same price
            List <Class_BuyOrder> tmp   = company.getBuyOrders();
            var grpBuyOrders            = tmp.GroupBy(x => x.getPrice());
            List <Class_SellOrder> tmp2 = company.getSellOrders();
            var grpSellOrders           = tmp2.GroupBy(x => x.getPrice());

            //workout max possible length using buyordersize and sellordersize
            int size = 0;

            if (company.getBuyOrderSize() > company.getSellOrderSize())
            {
                size = company.getBuyOrderSize();
            }
            else
            {
                size = company.getSellOrderSize();
            }

            //for loop to add data to each row of the datagrid
            for (int i = 0; i < size; i++)
            {
                double buyVolume  = 0;
                int    buyCounter = 0;
                double buyPrice   = 0;

                //workout out the volume, price and size of each order buy group
                if (i < grpBuyOrders.Count())
                {
                    buyPrice = grpBuyOrders.ElementAt(i).Key;
                    foreach (var value in grpBuyOrders.ElementAt(i))
                    {
                        buyVolume += value.getOrderSize();
                        buyCounter++;
                    }
                }

                double sellVolume  = 0;
                int    sellCounter = 0;
                double sellPrice   = 0;

                //workout out the volume, price and size of each order sell group
                if (i < grpSellOrders.Count())
                {
                    sellPrice = grpSellOrders.ElementAt(i).Key;
                    foreach (var value in grpSellOrders.ElementAt(i))
                    {
                        sellVolume += value.getOrderSize();
                        sellCounter++;
                    }
                }

                //if a row contains seller order only ie: more sellers than buyers so first 3 rows are blank at some point
                if (i >= grpBuyOrders.Count())
                {
                    if (sellCounter > 0)
                    {
                        dataGridView1.Rows.Add("", "", "", sellPrice, sellVolume, sellCounter);
                    }
                }

                //if a row contains buyer order only ie: more buyers than selles so first 2 rows are blank at some point
                else if (i >= grpSellOrders.Count())
                {
                    if (buyCounter > 0)
                    {
                        dataGridView1.Rows.Add(buyCounter, buyVolume, buyPrice);
                    }
                }

                //if both buy and sell orders in row
                else
                {
                    if (buyCounter > 0 && sellCounter > 0)
                    {
                        dataGridView1.Rows.Add(buyCounter, buyVolume, buyPrice, sellPrice, sellVolume, sellCounter);
                    }
                }

                //limit of the top 10 so break out of the for loop
                if (i == 9)
                {
                    break;
                }
            }
        }