Category: JavaScript

Dear Andrew,

Thank you for the past answers. I have a new question. I have a heatmap with 2 line charts at its left aand top position. the top line chart plot the horizontal values where the mouse if hovering and left chart displays vertical values from the mouse position.

This is working great, but the issue is the heatmap is not always square and I am trying the aligh the line charts with the heatmap dimensions

two issues,

1. the heatmap X/Y dimension are not always same, in fact I have a function which listens to the changing heatmap zoom factor and makes sure the X/Y are always “square” as we want to show the heatmap with square pixels. (see video #2) https://youtu.be/wXStF-7bWsw

2. As I dynamically chage the size of the plot the… the proportion of actual chart area to axis lable changes thus varying the overlap. (see video #1) https://youtu.be/loAVpYSRJ38

Let me know if you need more information,

Best,

Pramod

Hi,

In my application I am using two charts for represent different values. I am using LegendModifier on the first chart. Is it possible when i uncheck the series on first chart and the same color series on second chart also need to hide from the second chart. Any event callback function available in LegendModifier ?

Hi,

I am facing another issue with dataLabels in latest version of Scichart. I saw another question with similar is already posted and the fix is released.

Can you check this code.

I tried to reproduce the issue with the vue js example code, codesandbox. But the issues is behaving differently in example code, codesandbox, and my existing project.

codesandbox: https://codesandbox.io/s/scichart-error-6xc6jw?file=/src/index.ts
codesandbox:- Text in the bottom area are displayed and top area no labes are displayed.

I am attaching the vue js file also. Please check the file also, On the example no labels are displayed.

I am attaching the video of my project also, Here the labels are invisible sometimes, sometimes the labels are showing not properly. Video Link: https://drive.google.com/file/d/1vZ0lO5xdmN9VfFGXMaoTPfTgqRytrEAl/view?usp=sharing

How to update the text Annotation in JavaScript. I can add the new Text annotation but I can’t update the old text Annotation. whether we have any option in sci chart for JavaScript.

Hi Andrew,

I have 2 independent questions,

Q1.
I have been working with uniform heatmap and I need a way to fix the aspect ratio to 1, for all resize, zoom events, is there an option in heatmap to fix an aspect ration? Please see the attached video
https://youtu.be/obhH6KLExYw

Q2.
I am trying to implement a lasso select method to select and highlight the heatmap data. I did not find lasso select in the documentation hence I went ahead and implemented my own method.

I am drawing an svg using D3 (offsetX and offsetY variables) and then adding it to the annotation as you will see in the video and trying to get all the hitTest data inside the lasso.

If I use the customAnnotation then heatmap is able to draw correct size and location of the SVG
customAnnotation:
https://youtu.be/gL34sAbxYSE

But it does not pan and zoom with the plot data. after looking through documentation I came across OverviewCustomResizableAnnotation which seems designed for zooming and panning with the data.

But while using the OverviewCustomResizableAnnotation the SVG size keeps changing during the update and is not located at the correct location relative to the data.

sciChartSurfaceRef.current.annotations.add(
new OverviewCustomResizableAnnotation({
id: "lassoSVG",
x1: shortestXinData,
y1: shortestYinData,
isEditable: false,
isSelected: false,
yCoordinateMode: ECoordinateMode.DataValue,
xCoordinateMode: ECoordinateMode.DataValue,
verticalAnchorPoint: EVerticalAnchorPoint.Top,
horizontalAnchorPoint: EHorizontalAnchorPoint.Left,
svgString: new XMLSerializer().serializeToString(svg.node())
})
)
OverviewCustomResizableAnnotation:
https://youtu.be/-AOJ9V3l-xI

Thanks,

Pramod

I have a top chart that is a heatmap and there is another bottom chart that is a temperature map. I want the heatmap not show any y-axis labels but still keep the x-axis start aligned from the left side. I tried turning off the y-axis lables (which I do not need in the heatmap), but that moves the heatmap to the left and not kept aligned with the bottom chart.

const yAxis = new NumericAxis(wasmContext, {
autoRange: EAutoRange.Always,
labelFormat: ENumericFormat.Decimal,
labelPrecision: 2,
labelPostfix: "C",
drawLabels: false
});
The above code hides the y-axis labels but also removes the space on the left side so the x-axis of both graphs does not remained aligned. I need a way to somehow keep the start of x-axis aligned for both top and bottom graphs.

Hi,
I’m trying to synchronize the pie chart and the line chart in React. I’ve already done this for two line graphs.

They both use the same data table. And I want to know if it’s possible, if when I zoom in on the line chart, it updates the Pie chart with the new range.

Thanks, (sorry for my english ^^)

Good afternoon. Please tell me how can I change the Z index of the annotations so that the box annotation can overlap the text. Now no matter how I try to do it, the text is always above the rectangles. Does the JS version have some layers with annotations that can be changed by they Z like in this question – https://www.scichart.com/questions/wpf/changing-an-annotations-z-index

Unfortunately, I did not find this functionality in the JS version.

I’m looking for some direction on how to implement a modifier that reacts to interaction (mouse up/down etc) with a charts axis

• User clicks on axis
• Provide callback for side effect when clicked

Thanks

Hello,

I need to customize the text for some points on a XyScatterRenderableSeries graph. The problem is that the dataLabelProvider available for XyScatterRenderableSeries is BaseDataLabelProvider, but it doesn’t have a metaDataSelector method and I can’t do it with it. Interestingly, using LineSeriesDataLabelProvider I was able to add text for the points I needed using metadata, but another problem arose. In this case, if there is only one point on the graph, the text will not be drawn.

Here is a small example of how text is drawn for different numbers of points. https://codepen.io/PodaRocheK/pen/jOXYGMJ?editors=0011

Can you advise me on how to display text near points more correctly in the case when I use XyScatterRenderableSeries and often this text should disappear or appear near some points. Thanks a lot!

I am considering applying server-side licensing for my javerScript application.

In the document below, there is a phrase “Our server-side licensing component is written in C++.”
(https://support.scichart.com/index.php?/Knowledgebase/Article/View/17256/42/)

However, there is only asp.net sample code on the provided github.
(https://github.com/ABTSoftware/SciChart.JS.Examples/tree/master/Sandbox/demo-dotnet-server-licensing)

I wonder if there is a sample code implemented in C++ for server-side licensing.

Can you provide c++ sample code?
Also, are there any examples to run on Ubuntu?

Hello,
How can I animate an update of a candle or a bar in an OHLC type charts? I use realtime stock chart like this example.
When i update candle it redraws immediately with new values. But i want it to be updated with animation.

Hi, I want to color the axis label by its value,

eg.
value < 0 -> show red color
value = 0 -> show gray color
value > 0 -> show green color

similar to this question, but in javascript platform, it seems the LabelProvider has function related to the value(string) formatting only. Is there any ways to styling the label? Thanks!

Hello,

I switched from NumericAxis to DateTimeNumericAxis to view x axis labels in hh:mm format. It is definitely showing the labels in this format which is what I wanted, but for some reason it always show “Jan 1” in the first label. I simply want to show hh:mm labels based on the X values. One thing to now is that this is a live updating chart, not static data.

What am I missing? attached is a picture showing the issue and a picture with the DateTimeNumericAxis configuration.

Thanks.
Sergio.

Hello, I am using SciChartJS and have a new requirement from our users as follows that I need help with the implementation. Any pointers from anyone would be a great help.

**Requirements: **

• Assume that x-axis is Time and y-axis is prices.
• There are multiple series in the chart (e.g., Bid Price, Ask Price)
• Allow user to select a time on xAxis using CTRL + CLICK
• When the user selects the time, show the rollover line and the tooltip for all series at the selected time
• This rollover line and tooltip should remain visible until the user selects a new time on the x-axis at which point the rollover tooltip should display the tooltip for the new point.

I started inheriting the RolloverModifier but couldn’t find an appropriate method to show the tooltip.

So, I started implementing the above feature using CustomModifierBase2d and adding a VerticalLineAnnotation for the rollover line. But again, struggling with the tooltip.

If someone could help me out or give me pointers, that would be highly appreciated.

Best Regards,
Sachin Patel.

Hello I have been having a difficult time getting the correct time displayed on my xAxis and labels.

Passing in an xValue to an OHLC data series of 60 and the setting cursorLabelFormat: ENumericFormat.Date_DDMMHHMM this should produce a label “01/01 00:01” With the year as 1970.

When the computers timezone is set to UTC + 0 this behaves as expected.

However when the computers timezone is set to anything negative (UTC – 7) the label is formatted as “31/12 00:01” with the year 1969. If scichart is trying to convert to local time I would expect a reading of “31/12 17:01” 1969.

And when the timezone is set to anything positive (UTC + 7) the label is formatted as it is UTC +0 “01/01 00:01” 1970 again I would expect the hour to corrispond to the UTC offset if scichart is trying to convert to local time.

Looking at the later case I would assume that no time conversion is taking place which is what I would prefer. But looking at the former case (UTC -X) there appears to be some manipulation happening somewhere, I just have not been able to find any documentation explaining this. Am I missing something to get this to work properly out of the box without a custom label provider?

Thank you,

Update:

I do not want to worry about timezones. I want sciChart to plot the time that I give it. Again this is acting as expected when the computer timezone is in anything greater than UTC 0. But when the computer timezone is less than UTC 0 the label and axes are showing a date 24 hours prior to what I give it.

See attached images for the error. Note the only change that is happening is changing the computer timezone from UTC – 4 to UTC + 4.

See below for code setting up the chart.

Why is changing the computer timezone affecting the data labels?

export async function example(element) {
    let { sciChartSurface, wasmContext } = chartInstances.hasOwnProperty(element.id) && chartInstances[element.id];

    // initialize sciChart and add created chart to chartInstances
    if (sciChartSurface === undefined) {
        const newContext = await SciChartSurface.create(element.id);
        sciChartSurface = newContext.sciChartSurface;
        wasmContext = newContext.wasmContext;
        chartInstances[element.id] = { sciChartSurface, wasmContext };
    }

    //create and add xAxis
    let xAxis = new CategoryAxis(wasmContext, {
        drawLabels: true,
        drawMajorTickLines: true,
        drawMinorTickLines: true,
        axisAlignment: EAxisAlignment.Bottom,
        autoRange: EAutoRange.Once,
        cursorLabelFormat: ENumericFormat.Date_DDMMHHMM,
        labelFormat: ENumericFormat.Date_DDMMYYYY,
    });

    sciChartSurface.xAxes.add(xAxis);

    //create and add yAxis
    let yAxis = new NumericAxis(wasmContext, {
        maxAutoTicks: 5,
        autoRange: EAutoRange.Always,
        growBy: new NumberRange(0.3, 0.11),
        axisAlignment: EAxisAlignment.Right,
        labelPrecision: 4
    });
    sciChartSurface.yAxes.add(yAxis);

    //add chart modifiers
    sciChartSurface.chartModifiers.add(new ZoomPanModifier({ xyDirection: EXyDirection.XDirection }));
    sciChartSurface.chartModifiers.add(new ZoomExtentsModifier({ xyDirection: EXyDirection.XDirection }));
    sciChartSurface.chartModifiers.add(new MouseWheelZoomModifier({ xyDirection: EXyDirection.XDirection }));
    sciChartSurface.chartModifiers.add(new RolloverModifier({ modifierGroup: "first", showTooltip: false }));
    sciChartSurface.chartModifiers.add(new CursorModifier(
        {
            crosshairStroke: "#9598a1",
            crosshairStrokeDashArray: [10, 5],
        }));

    //apply desired theme
    sciChartSurface.applyTheme(new SciChartJSDarkTheme());

    //create three bars 
    _ohlcDataSeries = new OhlcDataSeries(wasmContext, {
        xValues: [60,120,180], //1 min, 2 min, 3 min post epoch
        openValues: [10,10,10],
        highValues: [15,15,15],
        lowValues: [5,5,5],
        closeValues: [11,11,11],
        dataSeriesName: "PriceDataSeries"
    });

    //create and style fastCandRendSeries
    const fcRendSeries = new FastCandlestickRenderableSeries(wasmContext,
        {
            dataSeries: _ohlcDataSeries,
            strokeThickness: 1,
            dataPointWidth: 0.5,
            brushUp: "#50ff50B2",
            brushDown: "#ff5050B2",
            strokeUp: "#50ff50",
            strokeDown: "#ff5050",
            animation: new WaveAnimation({ fadeEffect: true, duration: 800 })
        });
    sciChartSurface.renderableSeries.add(fcRendSeries);
}

Hello,

Can you show this example(https://codepen.io/PodaRocheK/pen/yLGxGEL?editors=0011) and tell me, why metadata labels are not displayed in some cases? May be you can tell me how to do it correctly? A have similar chart with a lot of datapoints and can’t understand why labels show only in some time(20s or > 1m after start the chart)

Thank you!

What languages are wrappers for the licensing server in? Where can I get information on what c++ functions to call?

I am trying to build my application with Electron. When the Electron application is run, it will open the UI in the browser (not opened with chromium). I created two Electron applications with same codes but with different versions of SciChart (i.e. version 2 and version 3). When I run with the Electron application with SciChart v2, the SciChart can be loaded properly. When when I run the Electron application with SciChart v3, I got error (please refer to the screenshot) and the SciChart cannot be loaded. I am not sure what’s wrong. Do you have any idea?

The project is developed on SciChart JS.

The x axis is date time numeric and y axis is numeric.

There is a option for the user to select the x axis interval. The interval values are 5 Min, 10 Min, 15 Min, 30 Min, 1 Hour, 6 Hour, 12 Hour, Days, Weeks, Months & Years.

When the user the selects a interval in the select option, the x axis should be updated with the selected interval.

For Example, If the user selects the 5 Min in the select option, then the x axis interval should be 5 Min.

For 5 Min X Axis Interval

16-Jan-2023 07:00
16-Jan-2023 07:05
16-Jan-2023 07:10
16-Jan-2023 07:15
16-Jan-2023 07:20
16-Jan-2023 07:25
16-Jan-2023 07:30

For 1 Hour X Axis Interval

16-Jan-2023 07:00
16-Jan-2023 08:00
16-Jan-2023 09:00
16-Jan-2023 10:00
16-Jan-2023 11:00
16-Jan-2023 12:00
16-Jan-2023 13:00
16-Jan-2023 14:00

So let me know how to change the interval in the x axis (date time numeric) based on the selection.

I have attached the zip file which contains the HTML file.

I used NPM to complete the deployment and development validation of SCICHART JS, and I completed the demo as follows:

At present, I have two unresolved issues that we will make a purchase decision after they are resolved:
1、How to set the sampling rate for chart?
Using the wpf control, the sampling rate can be set through the “FifoCapacity” property of XyDataSeries, but I did not find this property in the JS control.

2、How to hide the preview of the SciChartOverview control?

       I don't want to display the data of the bound chart

Hi,

I am facing a issue with RolloverModifier. I have multiple charts in single window. For some points the lines over the chart are missing.

Please find the attached images for some examples and the code for reproduce the issue. on the attachment you can see that the line on some chart is missing when mouse on left and right corner area of the chart.

Posting again because on latest version also the same issue not resolved.
https://www.scichart.com/questions/js/rollovermodifier-in-multiple-chart-line-missing-on-some-areas

Hello, how do I remove the shadow from tooltips, generated by the VerticalSliceModifier?

Thanks!