Stock chart Navigator data

[Ling]

Hi,
I'm trying to figure out why the bar chart displayed in the navigator clusters together as the data in the chart increases over time. As time progresses, the bars cluster together. I would like them to be bars of 1 minutes intervals and that is the granularity of the data I provide. 

Secondly, how do I display tooltip to show the bar charts values in the navigator? As you can see, I've enabled tool-tips but nothing shows up.

Below is how I've configured the stock chart's navigator. The attached screenshot shows how the bar chart looks initially.

navigator: {
    series: {
        type: "column",
        field: "tradeVolume",
        categoryField: "tradeTime",
        tooltip: {
            visible: true
       },
        color: "#D2E399"
    },
    categoryAxis: {
        baseUnit: "minutes",
        baseUnitStep: "1",
        justified: true,
        labels: {
            visible: true
        }
    }
},

[Hristo Germanov]

Hi Ling,

1) Unfortunately this is a bug and currently there is no resolutions. We will try to resolve this issue for our future releases.

2) Tooltip for the navigator pane is not supported.

Regards,
Hristo Germanov
Telerik

 

 

[Ling]

Hi Hristo,
1) Do you know how many data points are needed for the bars to start clustering together? Is it a function of the number of data points? As the number of data points increase I start seeing very fat bars whose meaning I'm unable to comprehend.

2) Is there no way to show the actual values of the data in the navigator pane - let's say I switch from column to area type?

[Hristo Germanov]

Hi Ling,

1) The chart will get the second unit if the current unit has points < 200. Example: if you have 2 years the base unit will be months because 2 years contains 730 days. The stock chart navigator is not flexible because of his complexity. If you want to customize the navigator you need to create chart with two panes and in the second pane you can create selection with the options that you want. In this case you need to handle the events from the navigator and filter the other axes. Link to our examples: http://demos.telerik.com/kendo-ui/chart-api/selection.

2) The events from the navigator pane will be propagated to the selection. Because of that the navigator series haven't tooltip.

Regards,
Hristo Germanov
Telerik

 

 

[Ling]

Hristo,
Is there a technical reason for the 200 points limit? For a stock chart, if it cannot show at least 1 day's worth of data with 1 minute granularity, that isn't very useful (7 hours * 60 mins = 420 data points). If you look at lot of stock charts, you will see this much data. 

Is this something that can be addressed?

Thanks

[Hristo Germanov]

Hi Ling,

If you set minutes but your data is from 2 years period you will have too many points and the browser will crash. Because of that we have default configuration.

The problem is in the navigator and we will try to improve it for our future releases. Please excuse us for the inconvenience that this may cause.

Regards,
Hristo Germanov
Telerik

 

 

[Ling]

Hi Hristo,
I understand the scenario you are talking about and developers have to be careful about it. For my specific use case, if I could override the limit to a higher value, that would be neat. Is there a way I can override the default limitation?

Thanks,
Gesly

[T. Tsonev]

Hi,

The default number of points will depend on the width of the chart. It can be overridden by adjusting the maxDateGroups option:
$("#chart").kendoStockChart({
  categoryAxis: {
    maxDateGroups: 200
  }
});

Problem is, the labels are tied to the points and will overlap each other.
You can move them to a separate axis as in this snippet.

I hope this helps.

Regards,
T. Tsonev
Telerik

 

 

[Ling]

Setting the maxDateGroups works for me. Thanks.