Javascript 渲染图问题

这是我的数据集。我想在x轴上绘图：日期和y轴是用法。因此，我想绘制每天的总使用量。即按日期分组

如何使用dc.js实现这一点？我有类似的东西

var data = [{"id":"1000","usage":"9219","date":"2012-06-01","country":"US"},
          {"id":"1001","usage":"13399","date":"2012-06-01","country":"US"},
          {"id":"1002","usage":"13181","date":"2012-06-02","country":"CA"},
          {"id":"1003","usage":"13494","date":"2012-06-02","country":"US"},
          {"id":"1004","usage":"6252","date":"2012-06-03","country":"US"},
          {"id":"1005","usage":"9351","date":"2012-06-03","country":"JP"},
          {"id":"1006","usage":"13753","date":"2012-06-04","country":"CN"},
          {"id":"1007","usage":"5410","date":"2012-06-04","country":"US"},
          {"id":"1008","usage":"1957","date":"2012-06-05","country":"CA"}] 

---

但是它没有绘制我想要的内容。

您也可以共享图表初始化吗？理想情况下，您能为您的问题添加一个JSFIDLE吗？您可以将其用作fiddle的起点。显示的代码配置了crossfilter维度和组，但从未初始化DC.JS图。要么海报忘记初始化他的图表，要么他忘记在问题中包含相关代码。

var ndx = crossfilter(data);

var dateDim = ndx.dimension(function(d) {return d.date;});
var totalUsage = dateDim.group().reduceSum(function(d) {return d.usage;});