Setting Data Points with the Data tab
The Data tab is the primary interface for configuring the chart and it is fairly complex. It sets the fields that determine the coordinates of each axis as well as maps the data points. It also has four buttons for setting the properties of specialized charts. The Advanced button shows the default layout and is available for every report. The Group button is enabled when your report has a grouping section and the Cross-Tab button is enabled when there is a cross-tab object on the report. The default selection, Advanced, is shown in Figure 12-2.
Figure 12-2. The Data tab with the Advanced button selected.
The Advanced button is always available for every report. The other three buttons are only enabled when data related to their chart type is in the report. The Group button is enabled when there is at least one group in the report. The Cross-Tab button must have a cross-tab object within the same section that the chart is placed in. The OLAP button is enabled when there are one or more OLAP grids within the same section as the chart.
Each layout button on the Data tab creates a different type of chart. Although they are all on the same Data tab and appear to work together, they are completely independent. Only the last one selected is used to create the chart. For example, say that you set some properties on the Advanced tab. You then decide that you would rather use a Group chart instead. So you click on the Group button and change the settings. When you run the report, the chart displayed on the report will be a group chart and reflect those settings. The settings you made with the Advanced button are ignored. In fact, when you close this dialog box and save your settings, only the settings for the current button are saved and any settings that were made with the other buttons are discarded.
The Advanced button on the data tab has three sections. The Available Fields list shows all the fields that the chart can use. To the right of the field list is the On Change Of list that sets which field(s) will have their data plotted. Below that is the Show Value(s) list. It sets the field(s) whose values are plotted on the chart. These sections are described next in more detail.
People often ask why they can’t find a particular formula field in the Available Fields list. This is because some formulas are classified as second-pass formulas and are calculated at the same time that the chart is being printed. Since all the data for that formula may not be available then the chart can’t plot it. See Chapter 1 for more information about the two-pass report processing model and which formulas get calculated in each pass.
