viewPort Max/Min with date value

[Joseph Simonds]

I’m building a ocean tide chart.
I have tides for 14 days on a spline area chart.
The issue is it shows all 14 days at once.

I need to be able to set the default view port of the chart to one day, with the users ability to pan/scroll on xAxis (left right) to other days.

[Manoj Mohan]

@saltstrong,

You can programmatically zoom into a region by setting viewportMinimum and viewportMaximum.

To zoom into a certain region, there should be a minimum of 3-4 dataPoints – behavior is designed such that zooming is limited upto a certain region, so the user doesn’t end up zooming into a blank-region (region with no dataPoints). Due to this restriction, it’s not possible to pan chart as you zoom into the region with just 1 dataPoint.

——-
Manoj Mohan
Team CanvasJS

[Joseph Simonds]

How would you setup a zoom for a date/time value on the xAxis?

[Manoj Mohan]

@saltstrong,

You can set the viewportMinimum as viewportMinimum: new Date(2019,03,14) and viewportMaximum as viewportMaximum:new Date(2019,04,14) to achieve zooming programmatically over data/time axisX type.

——-
Manoj Mohan
Team CanvasJS

[canvasjsUser001]

Hey @Manoj Mohan

Can you share a jsfiddle example that viewportMinimum works with time?

I tried 2 different ways, one is have x value as timestamp, and set xValueType: “dateTime”. like following

  {
  "type": "line",
  "axisX": [
    {
      "viewportMaximum": 1611186373807,
      "viewportMinimum": 1611182782013
    }
  ],

  "data": [
    {
      "markerType": "circle",
     
      "type": "line",
      "xValueType": "dateTime",
      
     
      "dataPoints": [
        {
          "y": 101789,
          "x": 1611185700000,
        },
        {
          "y": 12834,
          "x": 1611186300000,
        }
      ],

    }
  ],

}

But it doesn’t set the range to my desired value. However if I comment out xValueType: "dateTime", it will work because x value got treated as number.

I tried to set x and viewportMinimum to Date object like viewportMinimum: new Date(2019,03,14), but it still doesn’t work.

[Manoj Mohan]

@canvasjsuser001,

Thanks for reporting the use-case. We will fix this issue in our future versions. However, you can work-around the issue by setting minimum property of axisX as shown in this JSFiddle.

—-
Manoj Mohan
Team CanvasJS