ScaleGridOptionsBase.CustomAggregateFunction Property

Gets or sets the custom aggregate function callback that calculates the aggregated values.

Namespace: DevExpress.XtraCharts

Assembly: DevExpress.XtraCharts.v20.2.dll

NuGet Packages: DevExpress.Charts, DevExpress.WindowsDesktop.Charts

Declaration

C#

[Browsable(false)]
public CustomAggregateFunction CustomAggregateFunction { get; set; }

VB.NET

<Browsable(False)>
Public Property CustomAggregateFunction As CustomAggregateFunction

Property Value

Type	Description
CustomAggregateFunction	The custom aggregate function callback.

Property Paths

You can access this nested property as listed below:

Show 24 property paths

Object Type	Path to CustomAggregateFunction
Axis	.TimeSpanScaleOptions .CustomAggregateFunction
Axis2D	.TimeSpanScaleOptions .CustomAggregateFunction
Axis3D	.TimeSpanScaleOptions .CustomAggregateFunction
AxisBase	.TimeSpanScaleOptions .CustomAggregateFunction
AxisX	.TimeSpanScaleOptions .CustomAggregateFunction
AxisX	.QualitativeScaleOptions .CustomAggregateFunction
AxisX3D	.TimeSpanScaleOptions .CustomAggregateFunction
AxisX3D	.QualitativeScaleOptions .CustomAggregateFunction
AxisXBase	.TimeSpanScaleOptions .CustomAggregateFunction
AxisXBase	.QualitativeScaleOptions .CustomAggregateFunction
AxisY	.TimeSpanScaleOptions .CustomAggregateFunction
AxisY3D	.TimeSpanScaleOptions .CustomAggregateFunction
AxisYBase	.TimeSpanScaleOptions .CustomAggregateFunction
GanttAxisX	.TimeSpanScaleOptions .CustomAggregateFunction
GanttAxisX	.QualitativeScaleOptions .CustomAggregateFunction
PolarAxisX	.TimeSpanScaleOptions .CustomAggregateFunction
PolarAxisX	.QualitativeScaleOptions .CustomAggregateFunction
RadarAxis	.TimeSpanScaleOptions .CustomAggregateFunction
RadarAxisX	.TimeSpanScaleOptions .CustomAggregateFunction
RadarAxisX	.QualitativeScaleOptions .CustomAggregateFunction
RadarAxisY	.TimeSpanScaleOptions .CustomAggregateFunction
SecondaryAxisX	.TimeSpanScaleOptions .CustomAggregateFunction
SecondaryAxisX	.QualitativeScaleOptions .CustomAggregateFunction
SecondaryAxisY	.TimeSpanScaleOptions .CustomAggregateFunction
SwiftPlotDiagramAxis	.TimeSpanScaleOptions .CustomAggregateFunction
SwiftPlotDiagramAxisX	.TimeSpanScaleOptions .CustomAggregateFunction
SwiftPlotDiagramAxisXBase	.TimeSpanScaleOptions .CustomAggregateFunction
SwiftPlotDiagramAxisY	.TimeSpanScaleOptions .CustomAggregateFunction
SwiftPlotDiagramAxisYBase	.TimeSpanScaleOptions .CustomAggregateFunction
SwiftPlotDiagramSecondaryAxisX	.TimeSpanScaleOptions .CustomAggregateFunction
SwiftPlotDiagramSecondaryAxisY	.TimeSpanScaleOptions .CustomAggregateFunction

Example

Follow the steps below to create an aggregate function.

• Create a class that inherits the CustomAggregateFunction class.

• Implement its CustomAggregateFunction.Calculate method that then is called for each unique argument. Its groupInfo parameter is an object of the GroupInfo class and contains information about the argument and corresponding values:

  Property	Value Type
  groupInfo.Values1	Value (for common and bubble series), Value_1 (for range series), Low (for financial series)
  groupInfo.Values2	Weight (for bubble series), Value_2 (for range series), High (for financial series)
  groupInfo.Values3	Open (for financial series)
  groupInfo.Values4	Close (for financial series)

• Initialize the ScaleGridOptionsBase.CustomAggregateFunction property with an object of the newly created class.

• Set the ScaleGridOptionsBase.AggregateFunction property to Custom.

View Example

Form1.cs

private void Form1_Load(object sender, EventArgs e) {
    Series series = chartControl.Series["Random Data"];
    series.DataSource = GenerateData(100_000);
    series.ArgumentDataMember = "Argument";
    series.ValueDataMembers.AddRange("Value", "Value", "Value", "Value");

    XYDiagram diagram = chartControl.Diagram as XYDiagram;
    diagram.AxisX.DateTimeScaleOptions.AggregateFunction = AggregateFunction.Custom;
    diagram.AxisX.DateTimeScaleOptions.CustomAggregateFunction = new OhlcAggregateFunction();
}

class OhlcAggregateFunction : CustomAggregateFunction {
    public override double[] Calculate(GroupInfo groupInfo) {
        double open = groupInfo.Values1.First();
        double close = groupInfo.Values1.Last();
        double high = Double.MinValue;
        double low = Double.MaxValue;
        foreach (double value in groupInfo.Values1) {
            if (high < value) high = value;
            if (low > value) low = value;
        }

        return new double[] { high, low, open, close };
    }
}

Form1.vb

Private Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    Dim series As Series = chartControl.Series("Random Data")
    series.DataSource = GenerateData(100_000)
    series.ArgumentDataMember = "Argument"
    series.ValueDataMembers.AddRange("Value", "Value", "Value", "Value")

    Dim diagram As XYDiagram = TryCast(chartControl.Diagram, XYDiagram)
    diagram.AxisX.DateTimeScaleOptions.AggregateFunction = AggregateFunction.Custom
    diagram.AxisX.DateTimeScaleOptions.CustomAggregateFunction = New OhlcAggregateFunction()
End Sub

Private Class OhlcAggregateFunction
    Inherits CustomAggregateFunction

    Public Overrides Function Calculate(ByVal groupInfo As GroupInfo) As Double()
        Dim open As Double = groupInfo.Values1.First()
        Dim close As Double = groupInfo.Values1.Last()
        Dim high As Double = Double.MinValue
        Dim low As Double = Double.MaxValue
        For Each value As Double In groupInfo.Values1
            If high < value Then
                high = value
            End If
            If low > value Then
                low = value
            End If
        Next value

        Return New Double() { high, low, open, close }
    End Function
End Class

Related GitHub Examples

The following code snippet (auto-collected from DevExpress Examples) contains a reference to the CustomAggregateFunction property.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

C#

winforms-charts-implement-custom-aggregate-function/CS/DataAggregation/Form1.cs#L40

    diagram.AxisX.DateTimeScaleOptions.AggregateFunction = AggregateFunction.Custom;
    diagram.AxisX.DateTimeScaleOptions.CustomAggregateFunction = new OhlcAggregateFunction();
}

VB.NET

winforms-charts-implement-custom-aggregate-function/VB/DataAggregation/Form1.vb#L45

    diagram.AxisX.DateTimeScaleOptions.AggregateFunction = AggregateFunction.Custom
    diagram.AxisX.DateTimeScaleOptions.CustomAggregateFunction = New OhlcAggregateFunction()
End Sub