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Hi Jean Philippe.

A simple calculation to determine the memory requirement of SciChart is as follows.

40,000,000 points of X=Double, Y=Double requires 40,000,000 * 2 * 8 bytes just to store the data values. This is 640MBytes.

In addition, scichart needs some memory to store drawing commands and pixel coordinates (but not much).

Adding Metadata to X,Y points requires a further 4 bytes per data-point = 800MByte. Metadata is not added unless you add it, however for FIFO charts we have to create an empty Metadata array anyway. So it is possible to have 800MByte memory requirement for 40M points.

This is the raw amount of memory required to just store the data.

The limit per-process for 32-bit applications is 1.5GByte of memory and less if the heap is fragmented. So it is easy to get out of memory exception in 32-bit mode with this many data points.

What you can do is change the data-types.

1. Don’t use FIFO and don’t use metadata as this will discard the 4 bytes per data-point required for the metadata.
2. Use XType or YType int, float to reduce memory requirements.

e.g. 40M points, non FIFO, X,Y types float will require just 320MByte. A considerable reduction.

Alternatively, force your application to run in 64-bit mode when you have such high data requirements and everything will be OK!

Best regards,
Andrew

Thanks Andrew… I eliminated binding and range as the issue I think…

If I set AutoRange to Auto all is fine but not what I want, if I set AutoRange to Once – I have lines but then my binding will not update range properly. If I set it to Never binding works as expected but no Horizontal Lines… I’m not making any other code changes here just changing the AutoRange property.

I worked around this by manually drawing the lines from code and leaving AutoRange set to never.

If I ever figure it out I’ll post back.

Hi there,

DataSeries use these values internally to calculate Max and Min. For instance, if you have DataSeries<double, double> then YMax is set to Double.MinValue. This is so when the dataseries calculates YMax = Math.Max(YMax, y) it will always take Y after the first data-point is added.

May I ask, does it cause any specific problems? If so please treat DateTime.MinValue/MaxValue as ‘invalid values’.

Kind regards,
Andrew

Hey Chris,

I’m glad you figured it out, however this is also a feature native to SciChart.

See usage of Annotation.CoordinateMode = CoordinateMode.Relative.

In this mode, the X1,Y1 coordinates are from 0.0 to 1.0 where 0.0 is the left (or bottom) edge of the chart, and 1.0 is the right (or top) edge of the chart.

Furthermore, TextAnnotation can be anchored to the left / top (controlling where the X,Y coordinate operates from) using the HorizontalAnchorPoint and VerticalAnchorPoint properties.

Best regards,
Andrew

Hi Robert,

Thanks for your question.

The DragStarted, DragEnded, DragDelta events occur when an Annotation is being dragged by a user.

You can also subscribe to Thumb.DragStarted, DragDelta, DragCompleted events. These will signal the resize action when a user is resizing using the Resize Grips.

You can also create a new feature request if you wish specific resize events to be added and let people vote for this. Here is how to do it:
https://www.youtube.com/watch?v=cWa6bRCCAFE

Hope this helps.

Hi Egor,

Unfortunately it is not possible at the moment to use Palette Provider with FastMountainRenderableSeries. This may change in future releases.

Please check the page Change Series Color Dynamically using PaletteProvider as this has detailed info on how to use the PaletteProvider, and what series types are supported.

Kind regards,
Andrew

Update: we just noticed a bug(?) / issue where by the DateTimeNumericAxis won’t calculate deltas lower than 1 second.

This means that for resolutions below a second in SciChart.js you don’t get axis labels.

To fix this, in our Codepen we previously provided, we added a hint to suggest meaningful deltas that the axis can calculate. This is done as follows using the possibleDeltas property of an axis.

  const xAxis = new DateTimeNumericAxis(wasmContext, {
    axisTitle: "X Axis / DateTime",
    // Need to pass in smaller possible Deltas to allow for millisecond ticks
    possibleDeltas: [
        0.001,
        0.002,
        0.005,
        0.01,
        0.02,
        0.05,
        0.1,
        0.2,
        0.5,
        1,
        2,
        5,
        10,
        15,
        30,
        60,],
    labelProvider: new DynamicDateLabelProvider(),
  });

With that you can now zoom into milliseconds using SciChart.js and unix time stamps. Here’s a quick gif showing the zoom resolution down to milliseconds.

We’re going to address this in future releases, but for now, use possibleDeltas to extend precision of the date axis.

Best regards,
Andrew

Thank you for your answer.

Let me ask the question in a different way.

Is it possible to use RolloverModifier to show the cursor position in your sample app(WPF Chart Interaction with Annotations)?

If you use RolloverModifier, can you grab the annotation to move?

I want to know the way to use both showing the cursor position and grabing annotations in one mode.

        <s:SciChartSurface.RenderableSeries>
            <s:FastLineRenderableSeries DataSeries="{Binding ChartData}"
                                        IsDigitalLine="{Binding IsDigitalLine,
                                                                Mode=TwoWay}"
                                        ResamplingMode="{Binding SeriesResamplingMode}"
                                        Style="{StaticResource LineSeriesStyle}"
                                        s:CursorModifier.SnapToSeries="True"
                                        s:RolloverModifier.TooltipContainerStyle="{StaticResource TooltipStyle}"
                                        s:RolloverModifier.TooltipTemplate="{StaticResource TooltipDataTemplate}" />
        </s:SciChartSurface.RenderableSeries>

Here is the example I got from the SDK, but there is no example about how to do it in a MVVM pattern project.

Hi there,

Thanks for your question.
Unfortunately, the behaviour you are looking for is not supported by SciChart out of the box.
Our heatmap dataseries metadata has a different format, so the behaviour of selecting data points from its metadata is a bit complicated, and it is not implemented in the current version.

You may submit this as a feature request. To see how to submit a feature request and how are they prioritized, please read here:
https://www.scichart.com/feedback-policy/

Thank you for your reply.

And getting the code of SciChart.Examples.ExternalDependencies from GitHub and customizing the OnCreateModifiers section.

Before：

        foreach (var exampleMod in exampleModifiers.ChildModifiers.Where(x => GetAppearceInToolbar((ChartModifierBase)x)))
        {
            if (HasToAddUserModifierToModifierGroup(exampleMod, devMods))
            {
                devMods.ChildModifiers.Add(exampleMod);
            }

            if (HasToAddUserModifierToModifierGroup(exampleMod, userMods))
            {
                userMods.ChildModifiers.Add(exampleMod);
            }
        }

After：

        foreach (var exampleMod in exampleModifiers.ChildModifiers.Where(x => GetAppearceInToolbar((ChartModifierBase)x)).Where(a => HasToAddUserModifierToModifierGroup(a, devMods)).ToList())
        {
            devMods.ChildModifiers.Add(exampleMod);
        }
        foreach (var exampleMod in exampleModifiers.ChildModifiers.Where(x => GetAppearceInToolbar((ChartModifierBase)x)).Where(a => HasToAddUserModifierToModifierGroup(a, userMods)).ToList())
        {
            userMods.ChildModifiers.Add(exampleMod);
        }

UPDATED

Hi there,

We have several articles on printing and exporting to bitmap or XPS/PDF etc…

Please see:

• Export chart from screen to bitmap
• Exporting chart with legend to bitmap
• Rendering chart to bitmap in memory
• Screenshots, XPS Printing, X-Axis Text Labels

The Screenshots, XPS Printing, X-Axis Text Labels article now has an updated sample which compiles against SciChart v3.0 so you can download it and get started.

Hope this helps!
Yuriy