How can you use multi-level nesting, like this example in d3, using dc.js?
var expensesTotalByDay = d3.nest()
.key(function(d) { return d.name; })
.key(function(d) { return d.date; })
.rollup(function(v) { return d3.sum(v, function(d) { return d.amount; }); })
.map(expenses);
console.log(JSON.stringify(expensesTotalByDay));
I know that dc.js uses d3, but I don't get how to use it. Is there an example/tutorial available?