Skip to main content

AutomaticDateTimeScaleOptions.AutomaticMeasureUnitsCalculator Property

Gets or sets the automatic date-time measure unit calculator.

Namespace: DevExpress.Xpf.Charts

Assembly: DevExpress.Xpf.Charts.v24.1.dll

NuGet Package: DevExpress.Wpf.Charts

Declaration

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

Property Value

Type Description
IDateTimeMeasureUnitsCalculator

An object of the class implementing the IDateTimeMeasureUnitsCalculator interface.

Example

The automatic date-time 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. Create a class that implements the IDateTimeMeasureUnitsCalculator interface and assign it to the AutomaticDateTimeScaleOptions.AutomaticMeasureUnitsCalculator property to use a custom measurement units calculation algorithm:

public class CustomAutomaticDateTimeMeasureUnitsCalculator : IDateTimeMeasureUnitsCalculator {
    public DateTimeMeasureUnit CalculateMeasureUnit(
        IEnumerable<Series> series, 
        double axisLength, int pixelsPerUnit, 
        double visualMin, double visualMax, 
        double wholeMin, double wholeMax
    ) {
        double rawMeasureUnit = ((visualMax - visualMin) * pixelsPerUnit / axisLength);
        return PickDateTimeMeasureUnit(rawMeasureUnit);
    }

    static int[] unitMultipliers = {
        1, 1000, 60, 60, 24, 7, 4, 3, 4
    };
    static DateTimeMeasureUnit PickDateTimeMeasureUnit(double milliseconds) {
        double valueStop = 1.0;
        for (int i = 0; i < unitMultipliers.Length; i++) {
            valueStop *= unitMultipliers[i];
            if (milliseconds <= valueStop)
                return (DateTimeMeasureUnit)i;
        }
        return DateTimeMeasureUnit.Year;
    }
}
See Also