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1 vote
0 answers
2k views

If I have a use case, where heatmap data can be sparse in time, and I’m zooming around and panning trough the chart, it is quite possible to end up missing heatmap data, because at certain zoom levels, the heatmap lines just disappear.

Any tips to make this not happen?

Codepen showing the issue: https://codepen.io/jrfv/full/KKbrBdN

Make sure to zoom out slowly, and/or pan around, you should see one, or both lines disappearing.

I would post a video, but doesn’t seem to be allowed here, I’ll post 2 images at slightly different zoom levels then

1 vote
2k views

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

0 votes
0 answers
4k views

My application supports two themes (dark/light) for the charts. The background of the chart will be set to black if the dark mode is applied, and white if the light mode applied. It works well with the line chart. But there is strange grey background appeared in the heatmap chart when light mode is applied (Please check the attached screenshots). The color of gradient stop of offset 0 (min. heatmap zValues) is set to transparent and it works well with the dark mode. Do you know what’s wrong in my case?

Dark theme object applied to the chart:

{...new SciChartJSDarkTheme(), ...{
        sciChartBackground: "#1c1c1c",
        axisTitleColor: "#dee2e6",
        labelBorderBrush: "#dee2e6",
        tickTextBrush: "#dee2e6",
        majorGridLineBrush: "#1F3D68",
        minorGridLineBrush: "#102A47",
    }

Light theme object applied to the chart:

{...new SciChartJSLightTheme(), ...{
        sciChartBackground: "#fff",
        axisTitleColor: "#333",
        labelBorderBrush: "#333",
        tickTextBrush: "#333",
    }}

Heatmap graditentStops:

[
    { offset: 1, color: COLORS.DARK_RED },
    { offset: 0.8, color: COLORS.RED },
    { offset: 0.6, color: COLORS.YELLOW },
    { offset: 0.5, color: COLORS.GREEN },
    { offset: 0.4, color: COLORS.BLUE },
    { offset: 0.01, color: COLORS.DARK_BLUE },
    { offset: 0, color: "Transparent" },
]
0 votes
2k views

I want to create a chart like the attached image file.
I want to mark points with different colors depending on the number of data corresponding to the x and y axes.
As a result of searching, there is a HeatmapColorPalette. Is it good to use this?
If there is a more suitable chart, please introduce it.
thank you

0 votes
0 answers
4k views

I am implementing a waterfall chart with non-uniforma heatmap. I found that the live update doesn’t work. I keep updating the zValues with live data but the chart just show 1 row of data. If I resize the chart (my heatmap is inside a resizable container), I can see the updated data (i.e. Each time I resize the chart, the chart updated and show updated data). Do you have any example of live updated non-uniform heatmap? Below are my codes:

Draw the heatmap:

const SPECTROGRAM_HEIGHT = 256;
const SPECTROGRAM_WIDTH = 100;

const { sciChartSurface, wasmContext } = await SciChartSurface.create("spectrogram-chart-root");

const xAxis = new NumericAxis(wasmContext, {
    axisTitle: "Frequency",
    axisTitleStyle: {
        fontSize: CHART_STYLE.AXIS_FONT_SIZE,
        fontFamily: "sans-serif",
        fontWeight: "bold"
    },
    labelStyle: {
        fontSize: CHART_STYLE.LABEL_FONT_SIZE,
        fontFamily: "sans-serif"
    },
    labelFormat: ENumericFormat.Decimal,
    labelPrecision: 6,
    cursorLabelFormat: ENumericFormat.Decimal,
    cursorLabelPrecision: 6,
    drawMajorBands: false,
});

const yAxis = new NumericAxis(wasmContext, {
    axisTitle: "Time",
    axisTitleStyle: {
        fontSize: CHART_STYLE.AXIS_FONT_SIZE,
        fontFamily: "sans-serif",
        fontWeight: "bold"
    },
    labelStyle: {
        fontSize: CHART_STYLE.LABEL_FONT_SIZE,
        fontFamily: "sans-serif"
    },
    drawMajorBands: false,
});

// Add XAxis and YAxis
sciChartSurface.xAxes.add(xAxis);
sciChartSurface.yAxes.add(yAxis);

const colorMap = new HeatmapColorMap({
    minimum: -200,
    maximum: -50,
    gradientStops: [
    { offset: 0, color: "Transparent" },
    { offset: 0.01, color: COLORS.DARK_BLUE },
    { offset: 0.4, color: COLORS.BLUE },
    { offset: 0.5, color: COLORS.GREEN },
    { offset: 0.6, color: COLORS.YELLOW },
    { offset: 0.8, color: COLORS.RED },
    { offset: 1, color: COLORS.DARK_RED },
    ]
});

// Create a Heatmap Data-series. Pass heatValues as a number[][] to the UniformHeatmapDataSeries
zValues = Array.from(Array(SPECTROGRAM_HEIGHT), () => Array(SPECTROGRAM_WIDTH).fill(-200));

const heatmapSeries = new NonUniformHeatmapRenderableSeries(wasmContext, {
    dataSeries: new NonUniformHeatmapDataSeries(wasmContext, { zValues: zValues, xCellOffsets: getHeatmapXOffset, yCellOffsets: getHeatmapYOffset }),
    colorMap: colorMap,
    useLinearTextureFiltering: true,
    fillValuesOutOfRange: true,
});

// Add heatmap to the chart
sciChartSurface.renderableSeries.add(heatmapSeries);

I simply return the index for testing in the getHeatmapXOffset and getHeatmapYOffset functions:

    const getHeatmapXOffset = (index) => {
    return index;
};

const getHeatmapYOffset = (index) => {
    return index;
};

Reset zValues when number of data point changed:

        spectrogramZValues = Array.from(Array(SPECTROGRAM_HEIGHT), () => Array(newWidth).fill(-200));
        heatmapSeries.dataSeries.setZValues(spectrogramZValues);
        sciChartSurface.zoomExtents();

Update the zValues array when there is new data (I tried to add call zoomExtens() after notifyDataChanged but still didn’t work):

    spectrogramZValues.shift();
    spectrogramZValues.push(newData);
    heatmapSeries.current.dataSeries.notifyDataChanged();
  • Quyen Sy asked 10 months ago
  • last active 10 months ago
0 votes
2k views

Is it possible to change the heatmap legend from vertical to horizontal?

  • Quyen Sy asked 10 months ago
  • last active 10 months ago
0 votes
2k views

I am trying to create a live updated non-uniform heatmap with uniform xStep but non-uniform yStep. But I got color mapping problem when I tried to create the non-uniform heatmap. The color showing in the chart doesn’t map with the ColorMap value. Below are my codes:

Draw the non-uniform heatmap:

const SPECTROGRAM_HEIGHT = 256;
    const SPECTROGRAM_WIDTH = 100;

    const { sciChartSurface, wasmContext } = await SciChartSurface.create("spectrogram-chart-root");

    const xAxis = new NumericAxis(wasmContext, {
        axisTitle: "Frequency",
        axisTitleStyle: {
            fontSize: CHART_STYLE.AXIS_FONT_SIZE,
            fontFamily: "sans-serif",
            fontWeight: "bold"
        },
        labelStyle: {
            fontSize: CHART_STYLE.LABEL_FONT_SIZE,
            fontFamily: "sans-serif"
        },
        labelFormat: ENumericFormat.Decimal,
        labelPrecision: 6,
        cursorLabelFormat: ENumericFormat.Decimal,
        cursorLabelPrecision: 6,
        drawMajorBands: false,
    });

    const yAxis = new NumericAxis(wasmContext, {
        axisTitle: "Time",
        axisTitleStyle: {
            fontSize: CHART_STYLE.AXIS_FONT_SIZE,
            fontFamily: "sans-serif",
            fontWeight: "bold"
        },
        labelStyle: {
            fontSize: CHART_STYLE.LABEL_FONT_SIZE,
            fontFamily: "sans-serif"
        },
        drawMajorBands: false,
    });

    // Add XAxis and YAxis
    sciChartSurface.xAxes.add(xAxis);
    sciChartSurface.yAxes.add(yAxis);

    const colorMap = new HeatmapColorMap({
        minimum: -200,
        maximum: -50,
        gradientStops: [
            { offset: 1, color: COLORS.DARK_RED },
            { offset: 0.8, color: COLORS.RED },
            { offset: 0.6, color: COLORS.YELLOW },
            { offset: 0.5, color: COLORS.GREEN },
            { offset: 0.4, color: COLORS.BLUE },
            { offset: 0.01, color: COLORS.DARK_BLUE },
            { offset: 0, color: "Transparent" },
        ]
    });

    // Create a Heatmap Data-series. Pass heatValues as a number[][] to the UniformHeatmapDataSeries
    zValues = Array.from(Array(SPECTROGRAM_HEIGHT), () => Array(SPECTROGRAM_WIDTH).fill(-200));

    const heatmapSeries = new NonUniformHeatmapRenderableSeries(wasmContext, {
        dataSeries: new NonUniformHeatmapDataSeries(wasmContext, { zValues: zValues, xCellOffsets: getHeatmapXOffset, yCellOffsets: getHeatmapYOffset }),
        colorMap: colorMap,
        useLinearTextureFiltering: true,
        fillValuesOutOfRange: true,
    });

    // Add heatmap to the chart
    sciChartSurface.renderableSeries.add(heatmapSeries);

I simply return the index for testing in the getHeatmapXOffset and getHeatmapYOffset functions:

const getHeatmapXOffset = (index) => {
    return index;
};

const getHeatmapYOffset = (index) => {
    return index;
};

I fill the zValues array with the minimum value -200, but the data displayed in the chart is COLORS.YELLOW. I don’t understand what’s wrong.

  • Quyen Sy asked 10 months ago
  • last active 10 months ago
1 vote
2k views

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

1 vote
2k views

I am implementing a heatmap. The data size of the heatmap would be changed. I update the UniformHeatmapDataSeries with the updated zValues according to this post.

https://www.scichart.com/questions/js/failed-to-update-the-zvalues-size-of-uniformheatmapdataseries-in-heatmap

There is no problem if I update the UniformHeatmapDataSeries with a larger size zValues array. However, when I update it with a smaller size zValues array, the heatmap width will be decrease (Please refer to my screenshots). How can I keep the heatmap always 100% width?

  • Quyen Sy asked 11 months ago
  • last active 11 months ago
1 vote
2k views

I am implementing a heatmap. The data size of the heatmap would be changed. When the data size changed, I will replace the zValues of the UniformHeatmapDataSeries with an updated array. But it doesn’t work for me. The heatmap data cannot be plotted after I updated the zValues array. Below are my codes to create the heatmap and update the zValues array.

Draw heatmap:

    const { sciChartSurface, wasmContext } = await SciChartSurface.create("spectrogram-chart-root");
    let xAxisNumberRange = new NumberRange(minFreq/maxFreq);

    spectrogram_xAxis.current = new NumericAxis(wasmContext, {
        axisTitle: "Frequency",
        axisTitleStyle: {
            fontSize: CHART_STYLE.AXIS_FONT_SIZE,
            fontFamily: "sans-serif",
            fontWeight: "bold"
        },
        labelStyle: {
            fontSize: CHART_STYLE.LABEL_FONT_SIZE,
            fontFamily: "sans-serif"
        },
        visibleRange: xAxisNumberRange,
        visibleRangeLimit: xAxisNumberRange,
        zoomExtentsRange: xAxisNumberRange,
        labelFormat: ENumericFormat.Decimal,
        labelPrecision: 2,
        cursorLabelFormat: ENumericFormat.Decimal,
        cursorLabelPrecision: 2,
        drawMajorBands: false,
    });

    // Add XAxis and YAxis
    sciChartSurface.xAxes.add(spectrogram_xAxis.current);
    sciChartSurface.yAxes.add(new NumericAxis(wasmContext, { isVisible: false }));

    // Create a Heatmap Data-series. Pass heatValues as a number[][] to the UniformHeatmapDataSeries
    spectrogramZValues.current = Array.from(Array(SPECTROGRAM_HEIGHT), () => Array(SPECTROGRAM_WIDTH).fill(-200));
    heatmapDataSeries.current = new UniformHeatmapDataSeries(wasmContext, {
        xStart: 0,
        xStep: 1,
        yStart: 0,
        yStep: 1,
        zValues: spectrogramZValues.current
    });

    colorMap.current = new HeatmapColorMap({
        minimum: -200,
        maximum: -50,
        gradientStops: gradientStopsArr.current
    });

    // Create a Heatmap RenderableSeries with the color map. ColorMap.minimum/maximum defines the values in
    // HeatmapDataSeries which correspond to gradient stops at 0..1
    const heatmapSeries = new UniformHeatmapRenderableSeries(wasmContext, {
        dataSeries: heatmapDataSeries.current,
        useLinearTextureFiltering: true,
        isSorted: true, 
        isEvenlySpaced: true, 
        containsNaN: false,
        colorMap: colorMap.current
    });

    // Add heatmap to the chart
    sciChartSurface.renderableSeries.add(heatmapSeries);

Update heatmap data:

        // Update the chart x-axis
        if (xAxisUpdateRequired) {
            let xAxisNumberRange = new NumberRange(newStartFreq, newStopFreq);
            spectrogram_xAxis.current.visibleRange = xAxisNumberRange;
            spectrogram_xAxis.current.visibleRangeLimit = xAxisNumberRange;
            spectrogram_xAxis.current.zoomExtentsRange = xAxisNumberRange;  

            // Reset the heatmap zValues
            heatmapDataSeries.current.clear();
            spectrogramZValues.current = Array.from(Array(SPECTROGRAM_HEIGHT), () => Array(newSampleSize).fill(-200));
            heatmapDataSeries.current.setZValues(spectrogramZValues.current);
        }
        // Update heatmap data
        spectrogramZValues.current.shift();
        spectrogramZValues.current.push(newSpecData);
        heatmapDataSeries.current.notifyDataChanged();
  • Quyen Sy asked 11 months ago
  • last active 11 months ago
1 vote
2k views

I am trying to add an axis annotation to a heatmap legend. When this annotation is dragged, the color mapping of the heatmap series and the heatmap legend will be changed. How can I modify the colorMap.gradientStops of the heatmap series and the heatmap legend while the chart is running?

  • Quyen Sy asked 1 year ago
  • last active 1 year ago
1 vote
2k views

I am implementing a heatmap chart and would like to allow users to adjust the color mapping of the heatmap by adding sliders to the heatmap legend (Please refer to the attached screenshot). Does SciChart support color slider for HeatmapLegend?

  • Quyen Sy asked 1 year ago
  • last active 1 year ago
1 vote
2k views

Hello,

I am trying to change the frequency range in the Y axis on the Heatmap to 100000 from 50000, but the plot does not seem to be working to scale to the proper frequency range on the Y axis. I expect the plot to keep the same scale around 20000 for the upper line when I change the upper scale to 100000, but the graph scales the upper line up to 40000. I’m using function Heatmap2DArrayDataSeries() and passing the series data along with TimeFunc() for mapping to X axis and FreqFunc() for mapping to Y axis. I made some changes to FreqFunc(), but it did not change the upper line to 20000. See below for my partial code. Thanks,

    protected override void OnDisplayLoaded()
    {
    ...
    ...
        _dopplersurface.YAxes[0].VisibleRange = YVisibleRange2; // YVisibleRange2 = {0, 100000}
        _surface.UpdateLayout();

    }

    private void PlotData()
    {
    ...
        ...
        heatmap2DArrayDataSeries = new Heatmap2DArrayDataSeries<DateTime, double, double>(_spectrogramBuffer, TimeFunc, FreqFunc);
        HeatmapRenderableSeries = heatmap2DArrayDataSeries;
    }

    double FreqFunc(int iy)
    {
        double FreqDelta = 1.0 / (time_queue[1] - time_queue[0]).TotalSeconds / (FFT_Points / 2.0);
        if (((FFT_Points / 2.0) * FreqDelta / 2) < (double)YVisibleRange2.Max); // FFT_Points = 1024
        {
            FreqDelta = FreqDelta * 2;
        }
        return iy * FreqDelta / 2; // Returns 0 if iy is 0 and 50000 if iy is 512
    }

    DateTime TimeFunc(int ix)
    {
        if (time_queue.Count > (ix * Step))
        {
            DateTime DateTimeTemp1 = time_queue[ix * Step];
            return DateTimeTemp1;
        }
        else
        {
            return time_queue[time_queue.Count - 1];
        }
    }
  • Hoa Duong asked 2 years ago
  • last active 1 year ago
1 vote
6k views

We are testing your Android Example application, andwe are trying to find out the capabilities of the 2d Heatmap chart.

I have found in your documentation that you have the “Heatmap Texture Filtering” feature, anyways I am not able to set it as true in the heatmap plot. (found on the [WPF Heatmap Chart documentation][1 )

Is this feature disabled in Android Charts?

I am trying to enable this filtering, but the modification on your example app does not compile.

I have already tried to modify other stuff on your heatmap example chart, and it works, but particularly in our application we need as a must this kind of feature. It will be finally something that helps us to decide if your SciChart library meet our requirement.

Thanks for your attention,

1 vote
3k views

I have a large data set that I can’t really load into memory at once so instead I am paging the data, grabbing only what I require plus a little buffer either side so that the graph always has something in it.

To implement paging I need to change the position at which the graph starts rendering, unfortunately it seems that it is not possible to change UniformHeatmapDataSeries.xStart as set in the constructor.

Is the only way around this to recreate the heatmap from scratch every time a new page is loaded or am I missing another trick?

0 votes
2k views

Error from chart in div chart1 Error: getNativeXValues is invalid for heatmap type series. Try getting or setting zValues instead
at UniformHeatmapDataSeries.BaseHeatmapDataSeries.getNativeXValues (BaseHeatmapDataSeries.js:430:1)

Help! Please!

0 votes
8k views
  1. Big Sur 11.6.
  2. Monterey 12.2.1
  3. Catalina 10.15.7 (late 2013 model)
    ![enter image description here][1]

sciChart version 1.4.1611

If you open the chart in the Firefox browser, then, strangely enough, everything works.

Is it related to the version of the library?

0 votes
2k views

Hi everyone! We have a problem, the chart does not start on macOS and Windows 11 operating systems – a black screen is displayed.

I have a license (javascript): The javascript license must work on all Windows/Linux/macOS browsers.
also for mobile browsers.

The problem is displayed in any browser.

The parameters of the MacBook on which the chart does not start are attached below in the screenshot.

What could be the problem?

enter image description here

0 votes
5k views

Hi,

I want to change the colormap so that the:
– minimum (blue) = 4095
– maximum (red) = 800

Also, I want to set 0 to either black or transparent.

I can easily change the min and max values, just wanting to change the color limit and set 0 = black.

Here is my code for creating the heatmap:

public void heatmap(){
    // Create a SciChartSurface
    SciChartSurface surface = new SciChartSurface(this);
    // Get a layout declared in "activity_main.xml" by id
    LinearLayout chartLayout = findViewById(R.id.chart_layout);
    // Add the SciChartSurface to the layout
    chartLayout.addView(surface);
    // Initialize the SciChartBuilder
    SciChartBuilder.init(this);
    // Obtain the SciChartBuilder instance
    final SciChartBuilder sciChartBuilder = SciChartBuilder.instance();
    final NumericAxis xAxis = sciChartBuilder.newNumericAxis()
            .withGrowBy(0.1, 0.1)
            .build();
    final NumericAxis yAxis = sciChartBuilder.newNumericAxis()
            .withGrowBy(0.1, 0.1)
            .build();
    final FastUniformHeatmapRenderableSeries heatmapRenderableSeries = sciChartBuilder.newUniformHeatmap()
            .withMinimum(4095)
            .withMaximum(800)
            .withCellTextStyle(sciChartBuilder.newFont().withTextSize(8).withTextColor(ColorUtil.White).build())
            .withDrawTextInCell(true)
            .withDataSeries(createDataSeries())
            .build();
    final SciChartSurface chart = surface;
    Collections.addAll(chart.getXAxes(), xAxis);
    Collections.addAll(chart.getYAxes(), yAxis);
    Collections.addAll(chart.getRenderableSeries(), heatmapRenderableSeries);
    Collections.addAll(chart.getChartModifiers(), sciChartBuilder.newModifierGroupWithDefaultModifiers().build());
}
  • Jazz Adams asked 3 years ago
  • last active 3 years ago
0 votes
3k views

Hello,
I want to create a heatmap sync with a CandlestickRenderableSeries which using DiscontinuousDateTimeAxis, is it possible to make heatmap column align with ohlc point?

  • ZHOU HANG asked 3 years ago
  • last active 3 years ago
0 votes
7k views

Hi , many of the charts provide a way to set the date on the x axis for the data series and that makes the axis match the DataSeries value defined for that axis, but for heatmap dataseries when you define xType as date the xAxis of type date is not displaying on surface, I don’t know what I’m doing wrong and there is no sample for dates on GitHub , the samples only use int , would be great if you can provide a date sample for the heatmap , thanks

0 votes
3k views

Hi, I noticed that Heattexture: [object Object] is logged hundreds/thousands of times while interacting with a heatmap. This isn’t my console log, as it is a very simple implementation and there are no logs on my front end, with nothing called Heattexture in my repository.

I’m guessing that this is a leftover console log that needs to be removed, as it occurs in both my development and production Webpack builds.

Most of the time it does not cause any performance issues, but once I did see the heatmap flickering at roughly the same rate of the console log.

Screenshot attached.

Thanks!

0 votes
3k views

Hi,

Is it possible to specify that incoming zValues array matrix is an array of columns, instead of an array of rows?

e.g. if I pass this:

[
[1,2,3],
[4,5,6],
[7,8,9]
]

[1,2,3] is the first column, not the first row.

We want to avoid transposing this data manually before passing it to the heatmap, because our data arrives one column at a time via a websocket subscription, and the data is too large to efficiently re-transpose every time.

I can’t see anything in the docs or the code?

Thanks
Joe

0 votes
3k views

I am using UniformHeatMapDataSeries to plot a heat map in WPF/C#. However, the data is very large in size and as a result it is throwing OutOfMemoryException while populating the first parameter value of this data series. which is a two dimensional array TZ (generic).

As per definition:

public UniformHeatmapDataSeries(TZ[,] zValues, TX xStart, TX xStep, TY yStart, TY yStep, IPointMetadata[,] metadata = null);

Here I am filling this array with double[,] data.

This error is happening due to TZ double[,] is filled with very big size of data going out of max defined range of double 2D array size. Please suggest if I can replace the values of double[,] with any other data type which allow larger data.

  • Anil Soman asked 3 years ago
  • last active 3 years ago
0 votes
4k views

Hi SciChart-Team,

I’m currently rewrite one of our applications and move this from the leagacy .NET Framework to .NET Core.
I also replace the old SciChart.DirectX package and the DirectX Renderer plugin with the new VisualXcceleratorEngine witch is also based on DirectX.

In one chart we display a Order Spectrum as a heatmap (FastUniformHeatmapRenderableSeries) with linearly interpolated color between the cells. Thefore we activate the property UseLinearTextureFiltering.

But with the new VisualXcceleratorEngine is there no linearly interpolated color between the cells. Is this feature only available for the old DirectX Renderer plugin??

Thanks

0 votes
6k views

Hi,

I tried to implement a colormap view next to the heatmap chart. But couldn’t figure out how to set it up. It seems like it won’t work this way.

SciChartHeatmapColourMap colorMapView = new SciChartHeatmapColourMap(this);
colorMapView.findViewById(R.id.colorMapView);

I don’t know how Bindview works in the example code. Could you tell me how to link SciChartHeatmapColourMap to the view in layout xml?

Thanks.

  • Gang Xu asked 4 years ago
  • last active 4 years ago
0 votes
4k views

Hi,

I tried to initialize heatmap chart with NaN to make it transparent, but it doesn’t work that way. The color was blue, which is zero in the colormap. Is there a way to make it not showing any color?

Thanks,

public void initECMSciChart() {
    // initialize chart with NaN
    for (int i = 0; i < MATRIX_COLUMNS; i++) {
        for (int j = 0; j < MATRIX_ROWS; j++) {
            heatmap2DMatrix[i][j] = 0;
            heatmapDataSeries.updateZAt(i, j, Double.NaN);
        }
    }
    heatmapDataSeries.setStartX(0d);
    heatmapSurface.zoomExtentsX();
}
  • Gang Xu asked 4 years ago
  • last active 4 years ago
0 votes
4k views

Hello, I’ve been trying to create a SCIUniformHeatMap, but I only get a blank, black screen.
Can anyone recommend why colors and the graph aren’t showing up? Thanks

var ecmSurface: SCIChartSurface = SCIChartSurface()
var ecmDataSeries = SCIUniformHeatmapDataSeries(xType: .double, yType: .double, zType: .double, xSize: ReviewModeData.MATRIX_COLUMNS, ySize:ReviewModeData.MATRIX_ROWS)
var heatmapRenderableSeries: SCIFastUniformHeatmapRenderableSeries = SCIFastUniformHeatmapRenderableSeries()
private let countColors = 6
private var colorRGBArray: [UIColor] = [
UIColor(red: 0.0/255.0, green: 0.0/255.0, blue: 131.0/255.0, alpha: 1),
UIColor(red: 0.0/255.0, green: 0.0/255.0, blue: 255.0/255.0, alpha: 1),
UIColor(red: 0.0/255.0, green: 255.0/255.0, blue: 255.0/255.0, alpha: 1),
UIColor(red: 255.0/255.0, green: 255.0/255.0, blue: 0.0/255.0, alpha: 1),
UIColor(red: 255.0/255.0, green: 0.0/255.0, blue: 0.0/255.0, alpha: 1),
UIColor(red: 128.0/255.0, green: 0.0/255.0, blue: 0.0/255.0, alpha: 1)
]
for i in 0..<ReviewModeData.MATRIX_COLUMNS {
for j in 0 ..< ReviewModeData.MATRIX_ROWS {
ecmDataSeries.update(z: ecm2DMatrix[i][j], atX: i, y: j)
}
}
var colorZValueArray: [Double] = determineColorMapValues(clim1: 0, clim2: 1);
var colorMap = SCIColorMap(colors: colorRGBArray, andStops: colorZValueArray as [NSNumber])

//configure ECM heatmap
heatmapRenderableSeries.minimum = ReviewModeData.ECM_CLIM1
heatmapRenderableSeries.maximum = ReviewModeData.ECM_CLIM2
heatmapRenderableSeries.dataSeries = ecmDataSeries
heatmapRenderableSeries.colorMap = colorMap!

0 votes
10k views

I have two questions on rollover modifier.

One is the tooltip of the rollover is right under the finger on a heatmap chart. Can I move it to the top left section of the touch point?

Second question is how can I implement a callback function whenever Y axis of the rollover modifier changes?

Thanks for your attention in advance.

  • Gang Xu asked 4 years ago
  • last active 4 years ago
0 votes
8k views

Hi,
I would like to draw a polygon over a heatMap using an inherited class of UniformHeatMapDataSeries.
An example using FastHeatMapRenderableSeries was described here : https://www.scichart.com/questions/wpf/drawing-a-polygon-upon-a-heatmap-chart ,but it is now deprecated since SciCharts V5.

Instead of that, i tried to declare an inherited class of CustomRenderableSeries as shown here :

public class PolygonRenderableSeries : CustomRenderableSeries {
protected override void Draw(IRenderContext2D renderContext, IRenderPassData renderPassData)
{
base.Draw(renderContext, renderPassData);
}
}

What i need now is to pass a List of Polygons to this class in order to draw them directly. I know how to draw a polygon, but i don’t know how to override the renderPassData for adding polygons to it.

Could you help me about that ?
Best regards,

0 votes
5k views

I would like to add labels to contour lines as shown in this previous post.

https://www.scichart.com/questions/wpf/is-it-possible-to-do-contour-plots

I have created the heat map with contours, and now I want to programmatically add labels. To this end. I have created a contour series in my view model

        var contourSeries = new FastUniformContourRenderableSeries
        {
            DataSeries = dataSeries,
            ZMin = 0.0,
            ZMax = 50.0,
            ZStep = 4.0
        };

This is the same series as I have already plotted. I have looked through this object, trying to find the plotted contour lines, so I can calculate positions to put labels, but I have not found the data. Can you tell me how to extract the plotted contour curve data?

0 votes
6k views

Hello!

I am trying to render a HeatMap and align labels next to squares (see the attached image). However, I am running into two issues.

Firstly, I am using RenderTransform to shift labels so that they are aligned with the squares instead of being on the borders between them. It works, but does not look good as I resize the control.

Second, the axes render the last label outside the view. I tried setting VisualRange and VisualRangeLimit but it did not help. It hides the last data column (or row) and still displays the last label.

Any suggestions on how I can solve it?

I am attaching a sample project.

Thank you in advance!

0 votes
9k views

Hello!

I am trying to programmatically set a range for HeatmapColorPalette and attached HeatmapColorMap to min and max of my data.

Binding HeatmapColorPalette.Maximum to a property in my View Model works well. However, when I add HeatmapColorMap everything breaks, the heat map no longer responds to changes in View Model.

What am I doing wrong?

Here is my View:

<Window x:Class="SciChartHeatMap.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:local="clr-namespace:SciChartHeatMap"
    xmlns:s="http://schemas.abtsoftware.co.uk/scichart"
    d:DataContext="{d:DesignInstance Type=local:HeatMapViewModel, IsDesignTimeCreatable=True}"
    mc:Ignorable="d"
    Title="MainWindow" Height="450" Width="800">
<Grid>
    <Grid.Resources>
        <s:GradientStopsToLinearGradientBrushConverter x:Key="ColorsToLinearGradientBrushConverter"/>
    </Grid.Resources>
    <Grid.ColumnDefinitions>
        <ColumnDefinition/>
        <ColumnDefinition Width="Auto"/>
        <ColumnDefinition Width="Auto"/>
    </Grid.ColumnDefinitions>
    <Grid.RowDefinitions>
        <RowDefinition Height="Auto"/>
        <RowDefinition/>
    </Grid.RowDefinitions>
    <s:SciChartSurface Grid.Row="0" Grid.RowSpan="2">
        <s:SciChartSurface.RenderableSeries>
        <s:FastUniformHeatmapRenderableSeries x:Name="HeatMapSeries" DataSeries="{Binding Data}" Opacity="0.9">
            <s:FastUniformHeatmapRenderableSeries.ColorMap>
                <s:HeatmapColorPalette Maximum="{Binding ColorMaximum}">
                    <s:HeatmapColorPalette.GradientStops>
                        <GradientStop Offset="0" Color="DarkBlue"/>
                        <GradientStop Offset="0.2" Color="CornflowerBlue"/>
                        <GradientStop Offset="0.4" Color="DarkGreen"/>
                        <GradientStop Offset="0.6" Color="Chartreuse"/>
                        <GradientStop Offset="0.8" Color="Yellow"/>
                        <GradientStop Offset="1" Color="Red"/>
                    </s:HeatmapColorPalette.GradientStops>
                </s:HeatmapColorPalette>
            </s:FastUniformHeatmapRenderableSeries.ColorMap>
        </s:FastUniformHeatmapRenderableSeries>
        </s:SciChartSurface.RenderableSeries>
        <s:SciChartSurface.XAxis>
            <s:NumericAxis 
                FlipCoordinates="False" 
                ScientificNotation="None" 
                AutoTicks="False"
                MajorDelta="1"
                MinorDelta="0.5"
                AxisAlignment="Top"/>
        </s:SciChartSurface.XAxis>
        <s:SciChartSurface.YAxis>
            <s:NumericAxis 
                FlipCoordinates="True" 
                ScientificNotation="None"
                AxisAlignment="Left"/>
        </s:SciChartSurface.YAxis>
    </s:SciChartSurface>

    <!-- Enabling this will break the program
    <s:HeatmapColorMap
        Grid.Column="1"
        Grid.Row="0"
        Grid.RowSpan="2"
        Margin="5,0,5,0"
        HorizontalAlignment="Right"
        VerticalAlignment="Stretch"
        DataContext="{Binding Source={x:Reference Name=HeatMapSeries}, Mode=OneWay}"
        ColorMap="{Binding ColorMap.GradientStops, Converter={StaticResource ColorsToLinearGradientBrushConverter}}"
        Maximum="{Binding ColorMap.Maximum}"
        Orientation="Vertical">
    </s:HeatmapColorMap>
    -->

    <Label 
        Grid.Row="0" 
        Grid.Column="2" 
        Content="{Binding ColorMaximum}" 
        Width="50" 
        HorizontalContentAlignment="Center"/>
    <Slider 
        Grid.Column="2" 
        Grid.Row="1" 
        Orientation="Vertical" 
        Minimum="0" 
        Maximum="10" 
        HorizontalAlignment="Center"
        Value="{Binding ColorMaximum}"/>
</Grid>

The idea in this small example is for slider to control both HeatmapColorPalette.Maximum and s:HeatmapColorMap.Maximum

The code in my View Model is pretty simple:

private double mColorMax;

public double ColorMaximum
    {
        get => mColorMax;

        set
        {
            mColorMax = value;
            OnPropertyChanged();
        }
    }

My View Model implements INotifyPropertyChanged

I will appreciate any suggestions.

Thank you in advance!

0 votes
4k views

Hello,

I had previously commented on an existing issue, but wanted to bump here since it’s impeding development.

When adding a DataPointSelectionModifier to a chart surface containing a FastUniformHeatmapRenderableSeries with a UniformHeatmapDataSeries, an exception is thrown on a mouse drag.

The modifier is added simply with:

<s:SciChartSurface.ChartModifier>
    <s:ModifierGroup>
        <s:DataPointSelectionModifier/>
    </s:ModifierGroup>
</s:SciChartSurface.ChartModifier>

After adding this modifier and using my mouse to select a part of the heatmap, I get the following System.InvalidOperationException (stack trace below):

"Metadata for his type cannot be returned as an one-dimentional array. Please use the IPointMetadata[,] Metadata property"

I’m assuming this is happening because DataPointSelectionModifier was by default not meant for data series with 2D arrays, but I’m not sure how to follow the exception message “Please use the IPointMetadata[,] Metadata property”.

Ultimately I am trying to run a calculation on the selected subset of the heatmap. Any help would be appreciated and thanks in advance!

Stack trace:

  at SciChart.Charting.Model.DataSeries.Heatmap2DArrayDataSeries.BaseHeatmapDataSeries`3.SciChart.Charting.Model.DataSeries.IDataSeries.get_Metadata()
   at SciChart.Charting.ChartModifiers.DataPointSelectionModifier.UpdateState()
   at SciChart.Charting.ChartModifiers.DataPointSelectionModifier.KUB()
   at A.MEB.D[D](D D, Boolean I, Func`1 J)
   at SciChart.Charting.ChartModifiers.DataPointSelectionModifier.get_SelectedPointMarkers()
   at SciChart.Charting.ChartModifiers.DataPointSelectionModifier.DeselectAllPointMarkers()
   at SciChart.Charting.ChartModifiers.DataPointSelectionModifier.SelectManyPoints(Point startPoint, Point endPoint, SelectionMode selectionMode)
   at SciChart.Charting.ChartModifiers.DataPointSelectionModifier.OnModifierMouseUp(ModifierMouseArgs e)
   at SciChart.Charting.ChartModifiers.ModifierGroup.FTB(Action`2 D, ModifierEventArgsBase I)
   at SciChart.Core.Extensions.EnumerableExtensions.ForEachDo[T](IEnumerable`1 enumerable, Action`1 operation)
   at SciChart.Core.Utility.Mouse.MouseManager.GB(IPublishMouseEvents D, IReceiveMouseEvents I, MouseEventArgs J, MouseButtons M, Action`3 O)
   at SciChart.Core.Utility.Mouse.MouseManager.AEB.S(Object D, MouseButtonEventArgs I)
   at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target)
   at System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs)
   at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
   at System.Windows.UIElement.ReRaiseEventAs(DependencyObject sender, RoutedEventArgs args, RoutedEvent newEvent)
   at System.Windows.UIElement.OnMouseUpThunk(Object sender, MouseButtonEventArgs e)
   at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target)
   at System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs)
   at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
   at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args)
   at System.Windows.UIElement.RaiseTrustedEvent(RoutedEventArgs args)
   at System.Windows.Input.InputManager.ProcessStagingArea()
   at System.Windows.Input.InputManager.ProcessInput(InputEventArgs input)
   at System.Windows.Input.InputProviderSite.ReportInput(InputReport inputReport)
   at System.Windows.Interop.HwndMouseInputProvider.ReportInput(IntPtr hwnd, InputMode mode, Int32 timestamp, RawMouseActions actions, Int32 x, Int32 y, Int32 wheel)
   at System.Windows.Interop.HwndMouseInputProvider.FilterMessage(IntPtr hwnd, WindowMessage msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at System.Windows.Interop.HwndSource.InputFilterMessage(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
   at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
   at System.Windows.Threading.Dispatcher.LegacyInvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs)
   at MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam)
   at MS.Win32.UnsafeNativeMethods.DispatchMessage(MSG& msg)
   at System.Windows.Threading.Dispatcher.PushFrameImpl(DispatcherFrame frame)
   at System.Windows.Application.RunDispatcher(Object ignore)
   at System.Windows.Application.RunInternal(Window window)
   at Main.main(String[] _arg1) in ...\App.fs:line 13
  • jsacks asked 5 years ago
  • last active 5 years ago
0 votes
4k views

I was looking at the example given at this link for NonUniformHeatmapDataSeries in SciChart. In this example, the width and height of heatmap is given as h=4 and w=7. As I understand h is for Y axis and w is for X axis and data[,] is for Z axis. However, the counts in actual data filled for these axis are not matching wight h and w.

var xRangeMapping = new int[] { 0, 10, 20, 26, 36, 60, 72, 84 };   // 8 points for w
var yRangeMapping = new int[] { 100, 250, 390, 410, 600 };         // 5 points for h

What is the purpose of extra points added at first place (0 and 100)? Are these required to set the starting point for both axis?

Here is the code given at above link:

int w = 7, h = 4;
var data = new double[h, w];
double maxValue = double.MinValue;
for (int x = 0; x < w; x++)
    for (int y = 0; y < h; y++)
    {
        data[y, x] = 3.5 * ((h - y) * (w - x));
        maxValue = Math.Max(maxValue, data[y,x]);
    }
var xRangeMapping = new int[] { 0, 10, 20, 26, 36, 60, 72, 84 };
var yRangeMapping = new int[] { 100, 250, 390, 410, 600 };
var heatmapDataSeries = NonUniformHeatmapDataSeries<int, int, double>(data, i => xRangeMapping[i], i => yRangeMapping[i]);

// Apply the Heatmap DataSeries to a FastNonUniformheatmapRenderableSeries
var heatmapRenderableSeries = new FastUniformHeatmapRenderableSeries()
 {      
     ColorMap = new HeatmapColorPalette()
    {
        Maximum = maxValue,
        Minimum = 0,
        GradientStops = // exercise left to the reader
    }
 };
  • Anil Soman asked 5 years ago
  • last active 5 years ago
0 votes
4k views

I’m trying to add more intervals into the legend of the Heat map. So far it only displays 10, 8, 6, 4, 2, 0, but I would like to edit it to display the numbers 0-10. From what I understand, the TickProvider API only works with an X or Y axis so I’m not sure if there’s a way to add the function.

0 votes
0 answers
4k views

An empty chart is displayed if a custom axis id is configured for Heatmap series. Only “DefaultAxisId” seems to be supported.
Please suppport custom axis id with Heatmap series (with MVVM) to achieve the same behavior as other series types.

0 votes
4k views

To avoid arrays in LOH the UniformHeatmapDataSeries should use IList[] or Span instead of TZ[,].

  • Tobias asked 5 years ago
  • last active 5 years ago
0 votes
9k views

Hi there:

I am developing an application where the main chart is a heat map type one. I would like to have a custom cursor modifier to show some values of the x, y and z axes with limit digits. The problem is that so far I get these result:

Capture
EDIT: PLEASE INSERT AN IMAGE HERE

I would like to show only 1 decimal in the Z axis and 0 decimals en the X and Y axis. I have checked your modifiers demo but it seems to be not working for my heatmap chart. Any kind of advice about this issue would help me to have the application I am looking for.

The XAML of my chart is like this:

 <s:SciChartSurface x:Name="sciChart" Grid.Column="1" Grid.Row="3" Padding="0" BorderThickness="0" MouseDown="SciChart_MouseDown" Margin="0">
            <s:SciChartSurface.RenderableSeries>
                <s:FastUniformHeatmapRenderableSeries x:Name="heatmapSeries" 
                                                      Opacity="0.9"/>
            </s:SciChartSurface.RenderableSeries>

            <s:SciChartSurface.XAxis>
                <s:NumericAxis DrawMajorBands="True"  
                               DrawLabels="False"
                               TextFormatting="0N"
                               GrowBy="0, 1"
                               s:RolloverModifier.AxisLabelContainerStyle="{StaticResource AxisLabelStyle}" 
                               s:RolloverModifier.AxisLabelTemplate="{StaticResource AxisLabelTemplate}" 
                               s:CursorModifier.AxisLabelContainerStyle="{StaticResource CursorAxisLabelStyle}"/>
            </s:SciChartSurface.XAxis>

            <s:SciChartSurface.YAxis>
                <s:NumericAxis DrawMajorBands="True" 
                               GrowBy="0, 1"
                               DrawLabels="False" 
                               VisibleRange="0,249"  
                               TextFormatting="0"/>
            </s:SciChartSurface.YAxis>

            <s:SciChartSurface.ChartModifier>
                <s:ModifierGroup>
                    <s:RolloverModifier x:Name="RolloverModifier"
                                    IsEnabled="True"
                                    ShowTooltipOn="Always" />
                    <!--<s:CursorModifier IsEnabled="True" ShowTooltip="True" ShowTooltipOn="MouseOver"
                        ShowAxisLabels="true" SourceMode="AllSeries"/>-->
                    <s:CursorModifier x:Name="CursorModifier"
                                  IsEnabled="False"
                                  UseInterpolation="False"
                                  ShowAxisLabels="False"
                                  ShowTooltip="True"
                                  ShowTooltipOn="MouseOver"/>
                    <!--<s:VerticalSliceModifier IsEnabled="True">
                        <s:VerticalSliceModifier.VerticalLines>
                            <s:VerticalLineAnnotation IsEditable="false"
                                                  LabelPlacement="Axis"
                                                  ShowLabel="true"
                                                  LabelTextFormatting="0"/>
                        </s:VerticalSliceModifier.VerticalLines>
                    </s:VerticalSliceModifier>-->
                </s:ModifierGroup>

            </s:SciChartSurface.ChartModifier>
        </s:SciChartSurface>

Thanks in advanced.

2 votes
10k views

Hi guys,

I’ve been trying to select data points in my heat map for the whole without success. I’ve read, re-read and re-re-read the documentation, but I can’t figure out what I’m doing wrong.

Here’s the XAML.

...

<s:SciChartSurface.RenderableSeries>
    <s:FastUniformHeatmapRenderableSeriesForMvvm
        x:Name="heatmapSeries" 
        Opacity="0.9" 
        DataSeries="{Binding UniformHeatmapDataSeries}"
        s:DataPointSelectionModifier.IncludeSeries="True" >

        <s:FastUniformHeatmapRenderableSeriesForMvvm.ColorMap>
            <s:HeatmapColorPalette Maximum="60" Minimum="6">
                <s:HeatmapColorPalette.GradientStops>
                    <GradientStop Offset="0" Color="Transparent"/>
                    <GradientStop Offset="0.1" Color="DarkBlue"/>
                    <GradientStop Offset="0.2" Color="CornflowerBlue"/>
                    <GradientStop Offset="0.4" Color="DarkGreen"/>
                    <GradientStop Offset="0.6" Color="Chartreuse"/>
                    <GradientStop Offset="0.8" Color="Yellow"/>
                    <GradientStop Offset="1" Color="Red"/>
                </s:HeatmapColorPalette.GradientStops>
            </s:HeatmapColorPalette>
        </s:FastUniformHeatmapRenderableSeriesForMvvm.ColorMap>

        <s:FastUniformHeatmapRenderableSeriesForMvvm.PointMarker>
            <s:XPointMarker Fill="Pink" Width="5" Height="5"/>
        </s:FastUniformHeatmapRenderableSeriesForMvvm.PointMarker>

        <s:FastUniformHeatmapRenderableSeriesForMvvm.SelectedPointMarker>
            <s:TrianglePointMarker Fill="White" Width="12" Height="12"/>
        </s:FastUniformHeatmapRenderableSeriesForMvvm.SelectedPointMarker>

    </s:FastUniformHeatmapRenderableSeriesForMvvm>

    ...

</s:SciChartSurface.RenderableSeries>
...

Here’s the MVVM code.

...
class SelectedPointMetadata : IPointMetadata
{
    public bool IsSelected { get; set; }

    public event PropertyChangedEventHandler PropertyChanged;
}
...

double[,] heatMap = new double[heatMapHeight + glowRadius * 2, heatMapWidth + glowRadius * 2];
double[,] glowMatrix = this.getGlowEffectMatrix(glowRadius);

SelectedPointMetadata[,] selectablePoints = new SelectedPointMetadata[heatMapHeight + glowRadius * 2, heatMapWidth + glowRadius * 2];

for (int i = 0; i < spectrogram.SpectrogramAtoms.Count; i++) {
    var atom = spectrogram.SpectrogramAtoms[i];
    int x = Math.Min((int)(atom.Frequency.Hertz / frequencyStep) + glowRadius, heatMapHeight - 1);
    int y = Math.Min((int)(atom.Time.Seconds / xStep) + glowRadius, heatMapWidth - 1);
    this.applyEffectMatrix(x, y, atom.SNR, ref heatMap, ref glowMatrix, glowRadius);

}

var xBound = heatMap.GetLength(0);
var yBound = heatMap.GetLength(1);

Random rnd = new Random();

for (var i = 0; i < xBound; i++)
{
    for (var j = 0; j < yBound; j++)
    {
        var x = rnd.Next(1, 10);

        selectablePoints[i, j] = new SelectedPointMetadata() { IsSelected = false };

        if (x == 5)
        {
            selectablePoints[i, j].IsSelected = true;
        }

    }
}

this.UniformHeatmapDataSeries = new UniformHeatmapDataSeries<double, double, double>(
    heatMap,
    (-xStep * glowRadius),
    xStep,
    (-frequencyStep * glowRadius),
    frequencyStep,
    selectablePoints
    );

...

What am I missing?

0 votes
8k views

I have created a SciChartSurface with the width of 200 px. I have created a data series with data that corresponds to four vertical lines at 0 %, 25 %, 50 % and 75 % of width. When I set the data series’ width to 115 points all four vertical lines are clearly visible. However when I set the width to 116 points or more, the first line (at x == 0) disappears. Data series is still smaller than the renderable series width in px, so there is no reason for any of the vertical lines to go missing. Is this a bug, or did I configure something wrong?

Here is the xml layout:

<com.scichart.charting.visuals.SciChartSurface
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/chart"
    android:layout_width="200px"
    android:layout_height="match_parent"/>

Here is the code for MainActivity:

import android.os.Bundle
import android.support.v7.app.AppCompatActivity
import com.scichart.charting.model.dataSeries.UniformHeatmapDataSeries
import com.scichart.charting.visuals.SciChartSurface
import com.scichart.charting.visuals.renderableSeries.ColorMap
import com.scichart.drawing.utility.ColorUtil
import com.scichart.extensions.builders.SciChartBuilder
import kotlin.math.roundToInt

const val WIDTH = 116
const val HEIGHT = 50

class MainActivity : AppCompatActivity()
{
    override fun onCreate(savedInstanceState: Bundle?)
    {
        super.onCreate(savedInstanceState)

        SciChartSurface.setRuntimeLicenseKey(getString(R.string.sciChart_license))
        SciChartBuilder.init(this)

        setContentView(R.layout.activity_main)

        val chartSurface = findViewById<SciChartSurface>(R.id.chart)
        val chartBuilder = SciChartBuilder.instance()

        val xAxis = chartBuilder.newNumericAxis().build()
        val yAxis = chartBuilder.newNumericAxis().build()

        val dataSeries = UniformHeatmapDataSeries<Int, Int, Int>(Int::class.javaObjectType, Int::class.javaObjectType, Int::class.javaObjectType, WIDTH, HEIGHT)
        for (x in 0 until WIDTH)
        {
            for (y in 0 until HEIGHT)
            {
                val value = when (x)
                {
                    0,
                    (0.25 * WIDTH).roundToInt(),
                    (0.5 * WIDTH).roundToInt(),
                    (0.75 * WIDTH).roundToInt() -> 50
                    else                        -> 0
                }
                dataSeries.updateZAt(x, y, value)
            }
        }

        val series = chartBuilder.newUniformHeatmap()
            .withColorMap(ColorMap(intArrayOf(ColorUtil.DarkBlue, ColorUtil.CornflowerBlue, ColorUtil.DarkGreen, ColorUtil.Chartreuse, ColorUtil.Yellow, ColorUtil.Red), floatArrayOf(0f, 0.2f, 0.4f, 0.6f, 0.8f, 1f)))
            .withDataSeries(dataSeries)
            .build()

        chartSurface.suspendUpdates().use {
            chartSurface.xAxes.add(xAxis)
            chartSurface.yAxes.add(yAxis)
            chartSurface.renderableSeries.add(series)
        }
    }
}
0 votes
9k views

I have created a heatmap chart with values for the data series with four vertical lines of width 1. When the width of data series is smaller than width of SciChartSurface in pixels the four lines are clearly visible. However when I increase the width of data series to be bigger than the width in pixels, then some lines disappear, even though I’ve set the re-sampling mode to ResamplingMode.Max.

I wasn’t able to attach images to the post (got a Forbidden error), so I’ve uploaded them to Imagur:
Missing Lines
Visible lines

Here is the code from which the screen shots were made:

import android.os.Bundle
import android.support.v7.app.AppCompatActivity
import com.scichart.charting.model.dataSeries.UniformHeatmapDataSeries
import com.scichart.charting.visuals.SciChartSurface
import com.scichart.charting.visuals.renderableSeries.ColorMap
import com.scichart.data.numerics.ResamplingMode
import com.scichart.drawing.utility.ColorUtil
import com.scichart.extensions.builders.SciChartBuilder
import kotlin.math.roundToInt

const val WIDTH = 2000
const val HEIGHT = 50

class MainActivity : AppCompatActivity()
{
    override fun onCreate(savedInstanceState: Bundle?)
    {
        super.onCreate(savedInstanceState)

        SciChartSurface.setRuntimeLicenseKey(getString(R.string.sciChart_license))
        SciChartBuilder.init(this)

        setContentView(R.layout.activity_main)

        val chartSurface = findViewById<SciChartSurface>(R.id.chart)
        val chartBuilder = SciChartBuilder.instance()

        val xAxis = chartBuilder.newNumericAxis().build()
        val yAxis = chartBuilder.newNumericAxis().build()

        val dataSeries = UniformHeatmapDataSeries<Int, Int, Int>(Int::class.javaObjectType, Int::class.javaObjectType, Int::class.javaObjectType, WIDTH, HEIGHT)
        for (x in 0 until WIDTH)
        {
            for (y in 0 until HEIGHT)
            {
                val value = when (x)
                {
                    0,
                    (0.25 * WIDTH).roundToInt(),
                    (0.5 * WIDTH).roundToInt(),
                    (0.75 * WIDTH).roundToInt() -> 50
                    else                        -> 0
                }
                dataSeries.updateZAt(x, y, value)
            }
        }

        val series = chartBuilder.newUniformHeatmap()
            .withDataSeries(dataSeries)
            .withColorMap(ColorMap(intArrayOf(ColorUtil.DarkBlue, ColorUtil.CornflowerBlue, ColorUtil.DarkGreen, ColorUtil.Chartreuse, ColorUtil.Yellow, ColorUtil.Red), floatArrayOf(0f, 0.2f, 0.4f, 0.6f, 0.8f, 1f)))
            .withResamplingMode(ResamplingMode.Max)
            .build()

        chartSurface.suspendUpdates().use {
            chartSurface.xAxes.add(xAxis)
            chartSurface.yAxes.add(yAxis)
            chartSurface.renderableSeries.add(series)
        }
    }
}
0 votes
0 answers
6k views

Hi,

I am playing with the heatmap chart and stumbled upon an IndexOutOfRange exception when updating the chart.

I initialise my chart where Height=2 and Width=3:

var data = new double[Height, Width]; // 2 rows, 3 columns
double d = 0.0;
for (int y = 0; y < Height; y++)
{
    for (int x = 0; x < Width; x++)
    {
        data[y, x] = d++;
    }
}

heatmapSeries.DataSeries = new UniformHeatmapDataSeries<int, int, double>(data, 0, 1, 0, 1);

Calling the following line returns 5 which is equivalent to getting the value with data[1,2] (all good so far):

dataseries.GetZValue(yIndex: 1, xIndex: 2);

Now let’s update that value to, say 7.1, with:

dataseries.UpdateZValue(xIndex: 2, yIndex: 1, zValue: 7.1);

Executing the above line throws an IndexOutOfRangeException. Looking at the source code, the UpdateZValue() method does:

_zValues[xIndex, yIndex] = zValue;
// ...

No wonder why the exception gets thrown… I reckon it should be _zValues[yIndex, xIndex] = zValue; (xIndex and yIndex swapped).

0 votes
6k views

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-dev.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?

0 votes
10k views

I have created a HeatMap with the size of 25000 x 70. The application crashes with the following log:

E/libEGL: call to OpenGL ES API with no current context (logged once per thread)
E/libEGL: call to OpenGL ES API with no current context (logged once per thread)
E/libEGL: call to OpenGL ES API with no current context (logged once per thread)
D/OpenGLRenderer: Use EGL_SWAP_BEHAVIOR_PRESERVED: true
I/OpenGLRenderer: Initialized EGL, version 1.4
W/OpenGLRenderer: Failed to choose config with EGL_SWAP_BEHAVIOR_PRESERVED, retrying without…
D/EGL_emulation: eglCreateContext: 0x7faef90b6500: maj 2 min 0 rcv 2
D/EGL_emulation: eglMakeCurrent: 0x7faef90b6500: ver 2 0 (tinfo 0x7faf0489eec0)
D/EGL_emulation: eglMakeCurrent: 0x7faef90b6500: ver 2 0 (tinfo 0x7faf0489eec0)
D/EGL_emulation: eglCreateContext: 0x7faf04b65680: maj 2 min 0 rcv 2
D/EGL_emulation: eglMakeCurrent: 0x7faf04b65680: ver 2 0 (tinfo 0x7faf04b7e500)
E/emuglGLESv2_enc: device/generic/goldfish-opengl/system/GLESv2_enc/GL2Encoder.cpp:s_glTexImage2D:1908 GL error 0x501 A/libc: Fatal signal 11 (SIGSEGV), code 1, fault addr 0x41a10f90 in tid 2736 (GLThread 973)


Below is Kotlin code from my sample project that produces the error:

private const val WIDTH = 25000
private const val HEIGHT = 70

class MainActivity : AppCompatActivity()
{
    private lateinit var chartBuilder: SciChartBuilder

    override fun onCreate(savedInstanceState: Bundle?)
    {
        super.onCreate(savedInstanceState)

        SciChartSurface.setRuntimeLicenseKey(getString(R.string.sciChart_license))
        SciChartBuilder.init(this)
        chartBuilder = SciChartBuilder.instance()

        setContentView(R.layout.activity_main)
        val background = findViewById<ViewGroup>(R.id.background)

        val chartSurface = createChartSurface()
        background.addView(chartSurface)

        addPoints(chartSurface)
    }

    private fun createChartSurface(): SciChartSurface
    {
        val surface = SciChartSurface(this)

        val xAxis = chartBuilder.newNumericAxis().build()
        val yAxis = chartBuilder.newNumericAxis().build()

        surface.xAxes.add(xAxis)
        surface.yAxes.add(yAxis)

        surface.renderableSeries.add(createSeries(WIDTH, HEIGHT))

        return surface
    }

    private fun createSeries(width: Int, height: Int): FastUniformHeatmapRenderableSeries
    {
        val dataSeries = UniformHeatmapDataSeries(Int::class.javaObjectType, Int::class.javaObjectType, Float::class.javaObjectType, width, height)

        return chartBuilder.newUniformHeatmap()
            .withColorMap(ColorMap(intArrayOf(ColorUtil.DarkBlue, ColorUtil.CornflowerBlue, ColorUtil.DarkGreen, ColorUtil.Chartreuse, ColorUtil.Yellow, ColorUtil.Red), floatArrayOf(0f, 0.2f, 0.4f, 0.6f, 0.8f, 1f)))
            .withDataSeries(dataSeries)
            .build()
    }

    private fun addPoints(chartSurface: SciChartSurface)
    {
        @Suppress("UNCHECKED_CAST")
        val dataSeries = chartSurface.renderableSeries.first().dataSeries as UniformHeatmapDataSeries<Int, Int, Float>

        val xRange = 0 until WIDTH

        for (i in 0 until HEIGHT)
        {
            val values = xRange.map { (i + it).toFloat() }
            dataSeries.updateRangeZAt(0, i, values)
        }

        val renderableSeries = chartSurface.renderableSeries.first() as FastUniformHeatmapRenderableSeries
        renderableSeries.minimum = dataSeries.zValues.minimum.toDouble()
        renderableSeries.maximum = dataSeries.zValues.maximum.toDouble()
    }
}
0 votes
6k views

I am developing android app where i received data from pressure sensor(attached to arduino) and want to show it in scichart heatmap. i created succesfully scichart heatmap with IPaletteProvider. Now i want to update the heatmap with pressure sensor but currently i am unable to update my heatmap. Here is my Whole(PressureActivity code)code.

if (intent.getAction().equals(Constants.DATA)) {
String data = intent.getStringExtra(“DATA”);
if (data.contains(“ccccc”)) {
int index = data.indexOf(‘/’);
int indexx = data.indexOf(‘#’);
String d = data.substring((index + 1), indexx);
DoubleValues doubleValues=new DoubleValues(1);
doubleValues.add(Double.parseDouble(d));
dataSeries.updateZValues(doubleValues);
}
}

The above code is piece of android code where i actually received data from arduino and want to show it in heatmap so i update my dataSeries value. In my case
i use UniformHeatmapDataSeries<Integer, Integer, Double> dataSeries
But it did not work and shows only a rectangal of blue color and not updating with coming data.
Any one have any idea how to fix it.Thanks in advance.

  • mtg khan asked 6 years ago
  • last active 6 years ago
0 votes
7k views

Hello
Do heatmap dataseries support logarithmic axes? i have a heatmap chart and a line (pic 1), which need to be drawn in logarithmic scale, but i get no heatmap chart and the line is drawn correctly (pic 2) when switch axis type to logarithmic. Something i’m likely to get is on pic 3 .
thanks in advance

0 votes
10k views

Hi,

I’m trying to bind the maximum value of the HeatmapColorPalette in v5 in order to autorange the colormap to the data.

        <s:FastUniformHeatmapRenderableSeries x:Name="heatmapSeries" DataSeries="{Binding Data}" Opacity="0.9">
            <s:FastUniformHeatmapRenderableSeries.ColorMap>
                <s:HeatmapColorPalette Maximum="{Binding ColorMaximum}">
                    <s:HeatmapColorPalette.GradientStops>
                        <GradientStop Offset="0" Color="DarkBlue"/>
                        <GradientStop Offset="0.2" Color="CornflowerBlue"/>
                        <GradientStop Offset="0.4" Color="DarkGreen"/>
                        <GradientStop Offset="0.6" Color="Chartreuse"/>
                        <GradientStop Offset="0.8" Color="Yellow"/>
                        <GradientStop Offset="1" Color="Red"/>
                    </s:HeatmapColorPalette.GradientStops>
                </s:HeatmapColorPalette>
            </s:FastUniformHeatmapRenderableSeries.ColorMap>
        </s:FastUniformHeatmapRenderableSeries>

This previously worked in v4

            <s:FastHeatMapRenderableSeries x:Name="heatmapSeries" 
                                           DataSeries="{Binding Data}" 
                                           Opacity="0.9"
                                           Maximum="{Binding ColorMaximum}" 
                                           Minimum="{Binding ColorMinimum}"/>

The heatmap no longer refreshes to the new range when using the FastUniformHeatmapRenderableSeries instead of FastHeatMapRenderableSeries. Does anyone know why?

Regards,

  • Kevin Yeh asked 6 years ago
  • last active 6 years ago
1 vote
6k views

I have been reading about the performance of the heatmap chart. In some post I have found that the heatmap was going to be redesign to improve the performance, someone knows if this have happened?

My issue is that I’m trying to implement the waterfall example, but my 2d array is 50 x 31000 and when I try to render in realtime (with a loop of 500ms or below) it goes extremely slow and the whole app doesn’t respond.
When I switch the ResamplingMode to “Max” it improves a slightly, however the chart start to show some black gaps and color stripes like the data is not rendered properly.

If I run the same example with an smaller array like 100 x 100 none of this happens.

am I hitting the the boundaries of what can be done with the heatmap?

Are there any suggestions to improve the performance? (I have tried the StockThickness=1 and AntiAliasing=false)

If it is useful I can post some code.

0 votes
6k views

Hi,

InvalidatateParentSurface does’t seem to update the text in the heatmap cell however the change seems to be detected and the color value is getting updated. Can you please suggest how to fix this?

Attached is a sample.

Thanks,
-Tom

  • mijothomas asked 6 years ago
  • last active 6 years ago
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