histogram bucket sorting with crossfilter

index.js

function createDimensions(key) {
  var asc = xf.dimension(function (d) { return +(d[key]) })
  var desc = xf.dimension(function (d) { return -1 * (+(d[key])) })
  var sorter = new BucketSort(+(desc.top(1)[0][key]), +(asc.top(1)[0][key]), 100)
  var buckets = xf.dimension(function (d) { return sorter.getBucket(+d[key]) })
  var group = buckets.group()
  return {
    asc: asc,
    desc: desc,
    buckets: buckets,
    group: group
  }
}

function BucketSort(min, max, size) {
  var me = this
  var step = (max - min) / size
  me.buckets = []
  _.times(size, function() {
    me.buckets.push(min)
    min += step
  })
}

BucketSort.prototype.getBucket = function(value) {
  var idx = _.sortedIndex(this.buckets, value)
  return this.buckets[idx]
}

note: this isnt tuned for performance, but any perf tips are welcome!