XtraCharts provides you with the capability to calculate several built-in summary functions (MIN, MAX, SUM, AVERAGE, COUNT) against series values. In addition to the provided summary functions, you can create a custom one to calculate a summary value in any required way in your application. Moreover, the convenient approach of registering custom summary functions within a particular chart instance makes it possible for your end-users to use these functions in the Chart Wizard.
The following example demonstrates how to create a custom summary function, which returns a product of two values (Price * Count). To accomplish this task, it is required to create a summary function delegate and register it via the ChartControl.RegisterSummaryFunction (or WebChartControl.RegisterSummaryFunction) method.
The code below illustrates how this can be done.