This example demonstrates iOS Charts with X or Y logarithmic axis using SciChart.iOS.

The SCILogarithmicNumericAxis type can be set on the XAxis or YAxis of the SCIChartSurface in order to add a logarithmic scale to an iOS chart.

The Logarithmic Base may be set as a double value to change the Logarithmic Base of the axis, e.g. Log10, LogE, Log2.

Axis labels are formatted using Scientific notation with Superscript.

// LogarithmicAxisChartView.swift

//******************************************************************************
// SCICHART® Copyright SciChart Ltd. 2011-2018. All rights reserved.
//
// Web: http://www.scichart.com
// Support: support@scichart.com
// Sales:   sales@scichart.com
//
// LogarithmicAxisChartView.swift is part of the SCICHART® Examples. Permission is hereby granted
// to modify, create derivative works, distribute and publish any part of this source
// code whether for commercial, private or personal use.
//
// The SCICHART® examples are distributed in the hope that they will be useful, but
// without any warranty. It is provided "AS IS" without warranty of any kind, either
// expressed or implied.
//******************************************************************************

class LogarithmicAxisChartView: SingleChartLayout {

    override func initExample() {
        let xAxis = SCILogarithmicNumericAxis()
        xAxis.growBy = SCIDoubleRange(min: SCIGeneric(0.1), max: SCIGeneric(0.1))
        xAxis.scientificNotation = .logarithmicBase
        xAxis.textFormatting = "#.#E+0"
        
        let yAxis = SCILogarithmicNumericAxis()
        yAxis.growBy = SCIDoubleRange(min: SCIGeneric(0.1), max: SCIGeneric(0.1))
        yAxis.scientificNotation = .logarithmicBase
        yAxis.textFormatting = "#.#E+0"

        let dataSeries1 = SCIXyDataSeries(xType: .double, yType: .double)
        dataSeries1.seriesName = "Curve A"
        let dataSeries2 = SCIXyDataSeries(xType: .double, yType: .double)
        dataSeries2.seriesName = "Curve B"
        let dataSeries3 = SCIXyDataSeries(xType: .double, yType: .double)
        dataSeries3.seriesName = "Curve C"

        let doubleSeries1 = DataManager.getExponentialCurve(withExponent: 1.8, count: 100)
        let doubleSeries2 = DataManager.getExponentialCurve(withExponent: 2.25, count: 100)
        let doubleSeries3 = DataManager.getExponentialCurve(withExponent: 3.59, count: 100)
        
        dataSeries1.appendRangeX(doubleSeries1!.xValues, y: doubleSeries1!.yValues, count: doubleSeries1!.size)
        dataSeries2.appendRangeX(doubleSeries2!.xValues, y: doubleSeries2!.yValues, count: doubleSeries2!.size)
        dataSeries3.appendRangeX(doubleSeries3!.xValues, y: doubleSeries3!.yValues, count: doubleSeries3!.size)
        
        let line1Color: UInt32 = 0xFFFFFF00
        let line2Color: UInt32 = 0xFF279B27
        let line3Color: UInt32 = 0xFFFF1919
        
        let line1 = SCIFastLineRenderableSeries()
        line1.dataSeries = dataSeries1
        line1.strokeStyle = SCISolidPenStyle(colorCode: line1Color, withThickness: 1.5)
        line1.pointMarker = getPointMarker(size: 5, colorCode: line1Color)

        let line2 = SCIFastLineRenderableSeries()
        line2.dataSeries = dataSeries2
        line2.strokeStyle = SCISolidPenStyle(colorCode: line2Color, withThickness: 1.5)
        line2.style.pointMarker = getPointMarker(size: 5, colorCode: line2Color)
        
        let line3 = SCIFastLineRenderableSeries()
        line3.dataSeries = dataSeries3
        line3.strokeStyle = SCISolidPenStyle(colorCode: line3Color, withThickness: 1.5)
        line3.style.pointMarker = getPointMarker(size: 5, colorCode: line3Color)
        
        SCIUpdateSuspender.usingWithSuspendable(surface) {
            self.surface.xAxes.add(xAxis)
            self.surface.yAxes.add(yAxis)
            self.surface.renderableSeries.add(line1)
            self.surface.renderableSeries.add(line2)
            self.surface.renderableSeries.add(line3)
            self.surface.chartModifiers = SCIChartModifierCollection(childModifiers: [SCIPinchZoomModifier(), SCIZoomPanModifier(), SCIZoomExtentsModifier()])
            
            line1.addAnimation(SCISweepRenderableSeriesAnimation(duration: 3, curveAnimation: .easeOut))
            line2.addAnimation(SCISweepRenderableSeriesAnimation(duration: 3, curveAnimation: .easeOut))
            line3.addAnimation(SCISweepRenderableSeriesAnimation(duration: 3, curveAnimation: .easeOut))
        }
    }

    fileprivate func getPointMarker(size: Int, colorCode: UInt32) -> SCIEllipsePointMarker {
        let pointMarker = SCIEllipsePointMarker()
        pointMarker.width = Float(size)
        pointMarker.height = Float(size)
        pointMarker.strokeStyle = nil
        pointMarker.fillStyle = SCISolidBrushStyle(colorCode: colorCode)
        
        return pointMarker
    }
}

// LogarithmicAxisChartView.m

//******************************************************************************
// SCICHART® Copyright SciChart Ltd. 2011-2018. All rights reserved.
//
// Web: http://www.scichart.com
// Support: support@scichart.com
// Sales:   sales@scichart.com
//
// LogarithmicAxisChartView.m is part of the SCICHART® Examples. Permission is hereby granted
// to modify, create derivative works, distribute and publish any part of this source
// code whether for commercial, private or personal use.
//
// The SCICHART® examples are distributed in the hope that they will be useful, but
// without any warranty. It is provided "AS IS" without warranty of any kind, either
// expressed or implied.
//******************************************************************************

#import "LogarithmicAxisChartView.h"
#import "DataManager.h"

@implementation LogarithmicAxisChartView

- (void)initExample {
    SCILogarithmicNumericAxis * xAxis = [SCILogarithmicNumericAxis new];
    xAxis.growBy = [[SCIDoubleRange alloc] initWithMin:SCIGeneric(0.1) Max:SCIGeneric(0.1)];
    xAxis.scientificNotation = SCIScientificNotation_LogarithmicBase;
    xAxis.textFormatting = @"#.#E+0";

    SCILogarithmicNumericAxis * yAxis = [SCILogarithmicNumericAxis new];
    yAxis.growBy = [[SCIDoubleRange alloc] initWithMin:SCIGeneric(0.1) Max:SCIGeneric(0.1)];
    yAxis.scientificNotation = SCIScientificNotation_LogarithmicBase;
    yAxis.textFormatting = @"#.#E+0";
    
    SCIXyDataSeries * dataSeries1 = [[SCIXyDataSeries alloc] initWithXType:SCIDataType_Double YType:SCIDataType_Double];
    dataSeries1.seriesName = @"Curve A";
    SCIXyDataSeries * dataSeries2 = [[SCIXyDataSeries alloc] initWithXType:SCIDataType_Double YType:SCIDataType_Double];
    dataSeries2.seriesName = @"Curve B";
    SCIXyDataSeries * dataSeries3 = [[SCIXyDataSeries alloc] initWithXType:SCIDataType_Double YType:SCIDataType_Double];
    dataSeries3.seriesName = @"Curve C";
    
    DoubleSeries * doubleSeries1 = [DataManager getExponentialCurveWithExponent:1.8 count:100];
    DoubleSeries * doubleSeries2 = [DataManager getExponentialCurveWithExponent:2.25 count:100];
    DoubleSeries * doubleSeries3 = [DataManager getExponentialCurveWithExponent:3.59 count:100];
    
    [dataSeries1 appendRangeX:doubleSeries1.xValues Y:doubleSeries1.yValues Count:doubleSeries1.size];
    [dataSeries2 appendRangeX:doubleSeries2.xValues Y:doubleSeries2.yValues Count:doubleSeries2.size];
    [dataSeries3 appendRangeX:doubleSeries3.xValues Y:doubleSeries3.yValues Count:doubleSeries3.size];

    uint line1Color = 0xFFFFFF00;
    uint line2Color = 0xFF279B27;
    uint line3Color = 0xFFFF1919;
    
    SCIFastLineRenderableSeries * line1 = [SCIFastLineRenderableSeries new];
    line1.dataSeries = dataSeries1;
    line1.strokeStyle = [[SCISolidPenStyle alloc] initWithColorCode:line1Color withThickness:1.5];
    line1.pointMarker = [self getPointMarkerWithSize:5 colorCode:line1Color];

    SCIFastLineRenderableSeries * line2 = [SCIFastLineRenderableSeries new];
    line2.dataSeries = dataSeries2;
    line2.strokeStyle = [[SCISolidPenStyle alloc] initWithColorCode:line2Color withThickness:1.5];
    line2.pointMarker = [self getPointMarkerWithSize:5 colorCode:line2Color];
    
    SCIFastLineRenderableSeries * line3 = [SCIFastLineRenderableSeries new];
    line3.dataSeries = dataSeries3;
    line3.strokeStyle = [[SCISolidPenStyle alloc] initWithColorCode:line3Color withThickness:1.5];
    line3.pointMarker = [self getPointMarkerWithSize:5 colorCode:line3Color];
    
    [SCIUpdateSuspender usingWithSuspendable:self.surface withBlock:^{
        [self.surface.xAxes add:xAxis];
        [self.surface.yAxes add:yAxis];
        [self.surface.renderableSeries add:line1];
        [self.surface.renderableSeries add:line2];
        [self.surface.renderableSeries add:line3];
        self.surface.chartModifiers = [[SCIChartModifierCollection alloc] initWithChildModifiers:@[[SCIPinchZoomModifier new], [SCIZoomPanModifier new], [SCIZoomExtentsModifier new]]];
        
        [line1 addAnimation:[[SCISweepRenderableSeriesAnimation alloc] initWithDuration:3 curveAnimation:SCIAnimationCurve_EaseOut]];
        [line2 addAnimation:[[SCISweepRenderableSeriesAnimation alloc] initWithDuration:3 curveAnimation:SCIAnimationCurve_EaseOut]];
        [line3 addAnimation:[[SCISweepRenderableSeriesAnimation alloc] initWithDuration:3 curveAnimation:SCIAnimationCurve_EaseOut]];
    }];
}

- (SCIEllipsePointMarker *)getPointMarkerWithSize:(int)size colorCode:(uint)colorCode {
    SCIEllipsePointMarker * pointMarker = [SCIEllipsePointMarker new];
    pointMarker.height = size;
    pointMarker.width = size;
    pointMarker.strokeStyle = nil;
    pointMarker.fillStyle = [[SCISolidBrushStyle alloc]initWithColorCode:colorCode];
    
    return pointMarker;
}

@end

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