Horizontal line to show average in dygraph

dygraphs, javascript

Solution

As danvk mentioned before, try specifying the `"underlayCallback"` option within your `"new Dygraph()"` call. Use HTML Canvas context to draw the line.

Example below: (xmin and xmax are your unix epoch time in milliseconds)

var yavg= 50, xmin=1357016400000, xmax=1359694800000;
new Dygraph(document.getElementById('graph1'), data,{
  (....other options....),
  underlayCallback:function(ctx,area,dygraph){      
    var xl = dygraph.toDomCoords(xmin,yavg);
    var xr = dygraph.toDomCoords(xmax,yavg);
    ctx.strokeStyle= 'green';
    ctx.beginPath();
    ctx.moveTo(xl[0],xl[1]);
    ctx.lineTo(xr[0],xr[1]);
    ctx.closePath();
    ctx.stroke();       
 }});

Problem

I am trying to add a horizontal line to dygraph which already show my time series data. I have average of the complete data which I want to show as a static horizontal line on dygraph. Does anyone know how to do that simply. I already checked following links: http://dygraphs.com/tests/highlighted-region.html view-source:http://dygraphs.com/tests/crosshair.html There must be some simple solution to this

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