Meeting the Minimum Field Requirements
The Evaluate setting and Show Value setting work together to determine the X, Y and Z axis on each chart. Due to the fact that each type of chart can be unique in how it uses the fields in these settings to create the chart, it is important to know how many fields to put in each setting.
Charts have different requirements for the number of data values it needs to plot each point. For example, a line chart needs two values. The first value marks the time interval and the second value marks where on the chart the point will appear. A slightly more complicated chart, the X-Y Scatter chart, has different requirements. It needs a single value to set the intervals along the X-axis of the chart and it needs two values to mark where the point should appear on the chart. Table 10-4 shows the minimum number of fields required by each chart type.
Table 10-4. Required minimum number of fields for each type of chart.
| Chart Type | # On Change Of | # Show Value |
|---|---|---|
| Bar/Line/Area | 1 | 1 |
| Pie/Doughnut | 1 | 1 |
| Pie/Doughnut multiple | 1 | Many |
| 3D Riser | 1 | 1 |
| 3D Surface | 2 | 1 |
| 1 | Many | XY Scatter |
| 1 | 2 | Bubble |
| 1 | 3 | Stock |
| 1 | 2 | Stock with open/close marks |
| 1 | 4 |
The middle column, # of On Change Of fields, tells you how many fields are required when you have selected the On Change Of option in the drop-down box. This doesn’t apply if you selected either For Each Record or For All Records. This is because these selections automatically set the interval along the X-axis and you aren’t allowed to add new fields. However, if a chart type has a requirement of two fields, you won’t be able to use the For Each Record or For All Records options.
The last column, # of Show Value fields, tells you how many fields are required in the Show Values list. Each chart type requires at least one field and some charts allow you to add an unlimited number of fields. The only restriction is that it is limited to how many reasonably can fit on the chart.
