crossfilter dimension not rendering the counts

Question

I have a set of data that i would like to render on a line chart for the frequency

Data Parsing

var volumeChart = dc.barChart('#monthly-volume-chart');

var dateFormatSpecifier = '%Y-%m-%dT%H:%M:%S.000Z';
    var dateFormat = d3.timeFormat(dateFormatSpecifier);
    var dateFormatParser = d3.timeParse(dateFormatSpecifier);
    var numberFormat = d3.format('.2f');

    data.forEach(function (d) {
        d.dd = dateFormatParser(d.timestamp);
        d.minute = d3.timeMinute(d.dd)
        //coerce to number with a +
    });

Dimension grouping

var freqByMins = ndx.dimension(function (d) {
    return d.minute;
});
var aa = freqByMins.group()
console.log(aa.all())
var freqByMinsGroup = aa.reduceCount(function (d) {
    return d.minute;
});
console.log(freqByMinsGroup.all())

Looking at freqByMinsGroup.all() i get the following data

0: {key: Thu Feb 21 2019 05:29:00 GMT+0800 (Singapore Standard Time), value: 2}
1: {key: Thu Feb 21 2019 05:30:00 GMT+0800 (Singapore Standard Time), value: 5}
2: {key: Thu Feb 21 2019 05:31:00 GMT+0800 (Singapore Standard Time), value: 6}
3: {key: Thu Feb 21 2019 05:32:00 GMT+0800 (Singapore Standard Time), value: 3}
4: {key: Thu Feb 21 2019 05:33:00 GMT+0800 (Singapore Standard Time), value: 1}
5: {key: Thu Feb 21 2019 05:34:00 GMT+0800 (Singapore Standard Time), value: 1}
6: {key: Thu Feb 21 2019 05:35:00 GMT+0800 (Singapore Standard Time), value: 3}
7: {key: Thu Feb 21 2019 05:36:00 GMT+0800 (Singapore Standard Time), value: 4}
8: {key: Thu Feb 21 2019 05:38:00 GMT+0800 (Singapore Standard Time), value: 4}
9: {key: Thu Feb 21 2019 05:39:00 GMT+0800 (Singapore Standard Time), value: 7}
length: 10

Rendering charts

 volumeChart.width(960)
    .height(100)
    .margins({top: 10, right: 10, bottom: 20, left: 40})
    .dimension(freqByMins)
    .group(freqByMinsGroup)
    .transitionDuration(500)
    .elasticY(true)

    .x(d3.scaleTime().domain([new Date(2019, 2, 21, 5, 29, 0), new Date(2019, 2, 21, 5, 40, 0)]))
    .xAxis();

However, my crossfilter chart does not render any count.

Attached is an image

Gordon Gordon · Accepted Answer · 2019-02-26T01:55:09

Hard to say without a running example, because this looks mostly okay

But please try:

.xUnits(d3.timeMinutes) // to tell the chart how many entries
.x(d3.scaleTime()) // let the chart calculate the domain
.elasticX(true)

For example, if you were not in the Singapore timezone yourself, you could run into trouble. It's always easier to use elasticX/elasticY unless you need extra control.

I built a dummy fiddle with a fake group with your aggregated data, and it worked.

crossfilter dimension not rendering the counts

1 Answers