AutomaticNumericScaleOptions.AutomaticMeasureUnitsCalculator Property

Gets or sets the automatic numeric measure unit calculator.

Namespace: DevExpress.Xpf.Charts

Assembly: DevExpress.Xpf.Charts.v19.1.dll

Declaration

C#

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

VB.NET

<Browsable(False)>
Public Property AutomaticMeasureUnitsCalculator As INumericMeasureUnitsCalculator

Property Value

Type	Description
INumericMeasureUnitsCalculator	An object of the class implementing the INumericMeasureUnitsCalculator interface.

Example

The automatic numeric scale options provide the capability to use a custom measurement unit calculator to determine the current measurement unit if the predefined one does not fit your requirements. Design a class that implements the INumericMeasureUnitsCalculator interface and assign it to the AutomaticNumericScaleOptions.AutomaticMeasureUnitsCalculator property to use a custom measurement units calculation algorithm:

C#

public class CustomAutomaticNumericMeasureUnitsCalculator : INumericMeasureUnitsCalculator {
    public double CalculateMeasureUnit(
        IEnumerable<Series> series, 
        double axisLength, int pixelsPerUnit, 
        double visualMin, double visualMax, 
        double wholeMin, double wholeMax
    ) {
        double rawMeasureUnit = (visualMax - visualMin) * pixelsPerUnit / axisLength;
        return Math.Pow(10, GetDigitCount((int)Math.Abs(rawMeasureUnit)));
    }

    private static readonly int[] valueStops = {
        9, 99, 999, 9999, 99999, 999999, 9999999,
        99999999, 999999999, Int32.MaxValue
    };
    private static int GetDigitCount(int value) {
        for (int i = 0; ; i++)
            if (value <= valueStops[i])
                return i + 1;
    }
}

VB.NET

Class CustomAutomaticNumericMeasureUnitsCalculator
    Implements INumericMeasureUnitsCalculator
    Public Function CalculateMeasureUnit(
        series As IEnumerable(Of Series),
        axisLength As Double, pixelsPerUnit As Integer,
        visualMin As Double, visualMax As Double,
        wholeMin As Double, wholeMax As Double
    ) As Double Implements INumericMeasureUnitsCalculator.CalculateMeasureUnit
        Dim rawMeasureUnit = (visualMax - visualMin) * pixelsPerUnit / axisLength
        Return Math.Pow(10, GetDigitCount(CType(Math.Abs(rawMeasureUnit), Integer)))
    End Function

    Private Shared ReadOnly valueStops As Integer() = {
            9, 99, 999, 9999, 99999, 999999, 9999999,
            99999999, 999999999, Int32.MaxValue
    }
    Private Shared Function GetDigitCount(value As Integer) As Integer
        For i As Integer = 0 To valueStops.Length
            If (value <= valueStops(i)) Then Return i + 1
        Next
    End Function
End Class

XAML

<dxc:ChartControl>
    <dxc:XYDiagram2D>
        <dxc:XYDiagram2D.AxisX>
            <dxc:AxisX2D>
                <dxc:AxisX2D.NumericScaleOptions>
                    <dxc:AutomaticNumericScaleOptions>
                        <dxc:AutomaticNumericScaleOptions.AutomaticMeasureUnitsCalculator>
                            <view:CustomAutomaticNumericMeasureUnitsCalculator/>
                        </dxc:AutomaticNumericScaleOptions.AutomaticMeasureUnitsCalculator>
                    </dxc:AutomaticNumericScaleOptions>
                </dxc:AxisX2D.NumericScaleOptions>
            </dxc:AxisX2D>
        </dxc:XYDiagram2D.AxisX>
    </dxc:XYDiagram2D>
</dxc:ChartControl>

Related GitHub Examples

The following code snippet (auto-collected from DevExpress Examples) contains a reference to the AutomaticMeasureUnitsCalculator 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#

how-to-use-a-custom-numeric-measure-unit-in-automatic-scale-mode-t328193/VB/CustomNumericMeasureUnitsCalculatorSample/MainWindow.xaml#L17

<dxc:AutomaticNumericScaleOptions>
    <dxc:AutomaticNumericScaleOptions.AutomaticMeasureUnitsCalculator>
        <local:NumericMeasureUnitsCalculator/>