SummaryFunctionArgumentDescription Struct

Represents a structure which is intended to store information about an argument, passed to a custom summary function.

Namespace: DevExpress.XtraCharts

Assembly: DevExpress.XtraCharts.v18.1.dll

Declaration

C#

[RuntimeObject]
public struct SummaryFunctionArgumentDescription

VB.NET

<RuntimeObject>
Public Structure SummaryFunctionArgumentDescription

Example

The following example demonstrates how to create a custom summary function, which returns an OHLC point calculated by the passed array of values. To accomplish this task, create a SummaryFunction delegate and register it using the ChartControl.RegisterSummaryFunction method:

C#

// Declare the Financial summary function. 
private static SeriesPoint[] CalculateProductValue( 
        Series series, 
        object argument, 
        string[] functionArguments, 
        DataSourceValues[] values, 
        object[] colors
) { 
    string functionArgument = functionArguments[0]; 
    int lastIndex = values.Length - 1; 

    double open = Convert.ToDouble(values[0][functionArgument], CultureInfo.InvariantCulture); 
    double close = Convert.ToDouble(values[lastIndex][functionArgument], CultureInfo.InvariantCulture); 
    double high = Math.Max(open, close); 
    double low = Math.Min(open, close); 
    for (int i = 1; i < lastIndex; i++) { 
        high = Math.Max(high, Convert.ToDouble(values[i][functionArgument], CultureInfo.InvariantCulture)); 
        low = Math.Min(low, Convert.ToDouble(values[i][functionArgument], CultureInfo.InvariantCulture)); 
    } 
    // Return the result. 
    return new SeriesPoint[] { 
        new SeriesPoint(argument, high, low, open, close) 
    }; 
} 

private void Form1_Load(object sender, EventArgs e) { 
    chartControl.DataSource = new CurrencyRateLoader("../../Data/EurUsdRate.xml").Load();
    // Register the summary function in a chart. 
    chartControl.RegisterSummaryFunction( 
            name: "FINANCIAL", 
            displayName: "Financial", 
            resultScaleType: ScaleType.Numerical, 
            resultDimension: 4, 
            argumentDescriptions: new SummaryFunctionArgumentDescription[] { 
                new SummaryFunctionArgumentDescription("Value", ScaleType.Numerical) 
            }, 
            function: CalculateProductValue
    );

    Series series = chartControl.Series["EurUsd"]; 
    series.ArgumentDataMember = "DateTime";
    // Note that ValueDataMembers are not specified.
    series.SummaryFunction = "FINANCIAL([Value])"; 
}

VB.NET

' Declare the Financial summary function.
Private Shared Function CalculateProductValue(
        ByVal series As Series, 
        ByVal argument As Object, 
        ByVal functionArguments() As String, 
        ByVal values() As DataSourceValues, 
        ByVal colors() As Object
) As SeriesPoint()
    Dim functionArgument As String = functionArguments(0)
    Dim lastIndex As Integer = values.Length - 1

    Dim openValue As Double = Convert.ToDouble(values(0)(functionArgument), CultureInfo.InvariantCulture)
    Dim closeValue As Double = Convert.ToDouble(values(lastIndex)(functionArgument), CultureInfo.InvariantCulture)
    Dim highValue As Double = Math.Max(openValue, closeValue)
    Dim lowValue As Double = Math.Min(openValue, closeValue)
    For i As Integer = 1 To lastIndex - 1
        highValue = Math.Max(highValue, Convert.ToDouble(values(i)(functionArgument), CultureInfo.InvariantCulture))
        lowValue = Math.Min(lowValue, Convert.ToDouble(values(i)(functionArgument), CultureInfo.InvariantCulture))
    Next i
    ' Return the result.
    Return New SeriesPoint() { 
        New SeriesPoint(argument, high, low, open, close_Renamed) 
    }
End Function

Private Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    chartControl.DataSource = (New CurrencyRateLoader("../../Data/EurUsdRate.xml")).Load()
    ' Register the summary function in a chart.
    chartControl.RegisterSummaryFunction(
            name:= "FINANCIAL", 
            displayName:= "Financial", 
            resultScaleType:= ScaleType.Numerical, 
            resultDimension:= 4, 
            argumentDescriptions:= New SummaryFunctionArgumentDescription() { 
                New SummaryFunctionArgumentDescription("Value", ScaleType.Numerical) 
            }, 
            [function]:= AddressOf CalculateProductValue
    )

    Dim series As Series = chartControl.Series("EurUsd")
    series.ArgumentDataMember = "DateTime"
    ' Note that ValueDataMembers are not specified.
    series.SummaryFunction = "FINANCIAL([Value])"
End Sub

Related GitHub Examples

The following code snippets (auto-collected from DevExpress Examples) contain references to the SummaryFunctionArgumentDescription struct.

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#

how-to-create-a-custom-summary-function-e368/CS/Form1.cs#L33

// Create argument descriptions for the summary function.
SummaryFunctionArgumentDescription argument1Description =
    new SummaryFunctionArgumentDescription("Price", ScaleType.Numerical);

how-to-register-and-use-a-custom-summary-function-t257661/CS/RegisterSummaryFunctionExample/MainForm.aspx.cs#L45

chartControl.RegisterSummaryFunction(summaryFunctionName, summaryFunctionName, 1,
    new SummaryFunctionArgumentDescription[] {
        new SummaryFunctionArgumentDescription("Price", ScaleType.Numerical),

how-to-register-and-use-a-custom-summary-function-t257050/CS/RegisterSummaryFunctionExample/Form1.cs#L48

resultDimension: 4,
argumentDescriptions: new SummaryFunctionArgumentDescription[] {
    new SummaryFunctionArgumentDescription("Value", ScaleType.Numerical)

how-to-filter-points-in-a-chartcontrol-series-by-using-filtercontrol-e2340/CS/Form1.cs#L32

chartControl1.RegisterSummaryFunction("ExtFilter", "ExtFilter", 1,new SummaryFunctionArgumentDescription[] { },FilterData);
chartControl1.DataSource = nwindDataSet.Products;

VB.NET

how-to-create-a-custom-summary-function-e368/VB/Form1.vb#L35

' Create argument descriptions for the summary function.
Dim argument1Description As New SummaryFunctionArgumentDescription("Price", ScaleType.Numerical)
Dim argument2Description As New SummaryFunctionArgumentDescription("Count", ScaleType.Numerical)

how-to-register-and-use-a-custom-summary-function-t257661/VB/RegisterSummaryFunctionExample/MainForm.aspx.vb#L34

' Register the summary function in a chart.
chartControl.RegisterSummaryFunction(summaryFunctionName, summaryFunctionName, 1, New SummaryFunctionArgumentDescription() { _
    New SummaryFunctionArgumentDescription("Price", ScaleType.Numerical), _

how-to-filter-points-in-a-chartcontrol-series-by-using-filtercontrol-e2340/VB/Form1.vb#L35

chartControl1.RegisterSummaryFunction("ExtFilter", "ExtFilter", 1,New SummaryFunctionArgumentDescription() { },AddressOf FilterData)
chartControl1.DataSource = nwindDataSet.Products

how-to-register-and-use-a-custom-summary-function-t257050/VB/RegisterSummaryFunctionExample/Form1.vb#L39

' Register the summary function in a chart.
chartControl.RegisterSummaryFunction(name:= "FINANCIAL", displayName:= "Financial", resultScaleType:= ScaleType.Numerical, resultDimension:= 4, argumentDescriptions:= New SummaryFunctionArgumentDescription() { New SummaryFunctionArgumentDescription("Value", ScaleType.Numerical) }, [function]:= AddressOf CalculateProductValue)