Notes about creating high-low-close stock graphs

An open-high-low-close stock graph is a graph that is specifically designed for showing the opening, high, low, and closing prices of a stock. Each stock marker displays four separate values.

Figure 8-5 Example high-low-close stock graph

Description of the illustration gr_stock.gif

When you create high-low-close stock graphs (sometimes known as stock charts), follow these guidelines:

The data structure for open-high-low-close stock graphs is as follows:

• A group is a four-column set or, if data columns are shown as series, then a four-row set of data. It is represented by a single stock marker. If you show more than one group of data, the values for opening, high, low, and closing values should vary faster than the Time values. That is, the order of the columns (or rows) should be Monday Open, Monday High, Monday Low, Monday Close, Tuesday Open, Tuesday High, Tuesday Low, Tuesday Close, and so on. A group is labelled by an O1 tick label, such as Fri.

• A series is represented by all the markers that have the same color. Most stock graphs show only one series of data. A series is labeled by legend text, such as Stock A. The legend should appear, even if you have only one series of data.

Each group in an open-high-low-close stock graph has four values:

• The first value is the opening price. It determines the top of the stock marker.

• The second value is the high price, which determines the left arm of the stock marker.

• The third value is the low price, which defines the bottom of the stock marker.

• The fourth value is the closing price, which defines the right arm of the stock marker.

You need the following worksheet layout for a open-high-low-close stock graph:

• All graphs show numeric data only.

• The open-high-low-close stock graph must have at least four columns of data (or rows, if series are columns), in order Open, High Low, Close.

  If the data has fewer than four columns (or rows) of data, then the Graph bean displays a message about insufficient data, instead of displaying a graph.

  If the opening or closing price lies outside the high and low range, then the graph sends an AlertEvent to any registered AlertListeners. The ID for the AlertEvent is DATA_STOCK_OPEN_OR_CLOSE_OUT_OF_RANGE.

• To display stock data for more than one day, the data must be in multiples of four, such as four columns or rows for Monday, then four for Tuesday, and so on. If the last group does not have four columns (or rows), then the graph does not display that group. The graph notifies any registered AlertListeners of this problem by sending an AlertEvent, with DATA_PARTIAL_GROUP as its ID.

• Most open-high-low-close stock graphs have only one series of data. The series should be the name of the stock whose prices you show in the graph. You can have more than one series. However, if you do show more than one series and the prices of the different stocks overlap, then some stock markers obscure other stock markers.

• Time axis data must be regular, complete, and in ascending order. If it is not, then the graph displays a regular ordinal axis rather than a time axis. The graph recognizes time data that skips days when stocks are not traded.