dc.js barChart does not render

Question

I've been trying to re-create the complex reduce example, http://dc-js.github.io/dc.js/examples/complex-reduce.html, using my own data but cannot get the chart to render.

I copied these functions:

 function groupArrayAdd(keyfn) {
    var bisect = d3.bisector(keyfn);
    return function(elements, item) {
      var pos = bisect.right(elements, keyfn(item));
      elements.splice(pos, 0, item);
      return elements;
    };
  }

  function groupArrayRemove(keyfn) {
    var bisect = d3.bisector(keyfn);
    return function(elements, item) {
      var pos = bisect.left(elements, keyfn(item));
      if (keyfn(elements[pos]) === keyfn(item))
        elements.splice(pos, 1);
      return elements;
    };
  }

  function groupArrayInit() {
    return [];
  };

and then set up my dimension, group and chart:

  var monthKey = function(d) {
    return d.month;
  };

  var scoreValue = function(d) {
    return d.points_per_date;
  };

  var monthDimension = ndx.dimension(monthKey);

  var monthAvgGroup = monthDimension.group().reduce(groupArrayAdd(monthKey), groupArrayRemove(monthKey), groupArrayInit);


  function sumPoints(kv) {
    return d3.sum(kv.value, scoreValue);
  };

  var accessors = {
    sum: sumPoints
  };


  monthChart
    .width(400)
    .height(300)
    .x(d3.time.scale().domain([d3.min(data, function(d) {
      return d.month
    }), d3.max(data, function(d) {
      return d.month
    })]))
    .xUnits(d3.time.months)
    .valueAccessor(sumPoints)
    .elasticY(true)
    .brushOn(true)
    .controlsUseVisibility(true)
    .dimension(monthDimension)
    .group(monthAvgGroup);

the fiddle is https://jsfiddle.net/santoshsewlal/pa524yLc/. I think I'm messing up on setting the valueAccessor.
Any suggestions?

Thanks

Gordon Gordon · Accepted Answer · 2017-02-03T00:56:36

It's just a typo - in the HTML you gave the bar chart an id #test-month when it should just be test-month. The hash mark is just for selectors.

I'd also suggest offsetting the top of the x domain by 1 month because dc.js takes the domain very literally and does not automatically allow space for the bars:

.x(d3.time.scale().domain([d3.min(data, function(d) {
  return d.month
}), d3.time.month.offset(d3.max(data, function(d) {
  return d.month
}),1)]))

https://jsfiddle.net/pa524yLc/6/

The difference in scale between the bars is really huge - three of the bars look like they're missing but they're just really small. Wish that logarithmic scales worked better.

dc.js barChart does not render

1 Answers