Performance on very large data sets

[paulsUsername]

I have a standard graph with a very simple implementation, but my data sets are very large and I want them to be swipeable.

Is there anything I can do to help? Some data sets are over 30-40k data points, sometimes up to 70-80k. Ideally, I would like very high quality swiping performance.

If I had certainty of performance I would not be opposed to buying a license and or purchasing support.

[thierryH91200]

look at #3774 and #3699

i have resolved the problem

drawCircles is very long and dataSet.isDrawCirclesEnabled is not tested

charts/renderers/chartsRenderers/LineChartRenderer

in private func drawCircles(context: CGContext)

private func drawCircles(context: CGContext)
{
    guard
        let dataProvider = dataProvider,
        let lineData = dataProvider.lineData
        else { return }

    let phaseY = animator.phaseY

    let dataSets = lineData.dataSets

    var pt = CGPoint()
    var rect = CGRect()

    context.saveGState()

    for i in 0 ..< dataSets.count
    {
        guard let dataSet = lineData.getDataSetByIndex(i) as? LineChartDataSetProtocol else { continue }

        if !dataSet.isVisible || **!dataSet.isDrawCirclesEnabled** || dataSet.entryCount == 0
        {
            continue
        }

and

dataSet.drawCirclesEnabled = false

[paulsUsername]

To add:

Performance on Android is next to perfect despite using it on an older much lower performance device (Samsung A5).

But iOS, on an iPhone X, performance is terrible and completely unusable

[paulsUsername]

@thierryH91200 Thanks I'll have a look at them

[rmehta33]

I'm having a similar issue. Is there a way to set a maximum number of entries that can be displayed at once? Since zoomed out, 70k points look the same as 500 points.

[paulsUsername]

@rmehta33 chart.maxVisibleCount might be of use to you

[paulsUsername]

@thierryH91200 Thank you! I am seeing a drastic improvement in performance. Still would like to see it get even better but this is definitely a start. Thanks

[thierryH91200]

@paulsUsername i have add for the test

func printTimeElapsedWhenRunningCode(title:String, operation:()->()) {
    let startTime = CFAbsoluteTimeGetCurrent()
    operation()
    let timeElapsed = CFAbsoluteTimeGetCurrent() - startTime
    print("Time elapsed for \(title): \(timeElapsed) s.")
}

and

    printTimeElapsedWhenRunningCode(title:"drawExtras") {
        renderer.drawExtras(context: context)
    }

the result with the last version is Time elapsed for drawExtras: 3.9924609661102295 s. Time elapsed for drawExtras: 3.962438941001892 s.

and with 3.0.2

Time elapsed for drawExtras: 2.6941299438476562e-05 s. Time elapsed for drawExtras: 1.0013580322265625e-05 s.

the difference is ........... great

[liuxuan30]

@thierryH91200 any chance it can be forged into a pull request?

[paulsUsername]

@liuxuan30 I can do it If I can get permission to create a branch

[liuxuan30]

just point to master(preferred) or 4.0 branch

[Garenge]

you can call setVisibleXRangeMaximum after you set data.

[paulsUsername]

just point to master(preferred) or 4.0 branch

Sorry, I am terrible at this git stuff. Not my area of expertise so I'm probably not the best person for it. I can tell you though, the addition of:

    if !dataSet.isVisible || **!dataSet.isDrawCirclesEnabled** || dataSet.entryCount == 0

It makes a really big difference to performance.