Ex. 4 in Reactive Bar Chart Article

reactive_bar_example_4.js

function BarChart(svg) {
  this.width = $R.state(200);
  this.height = $R.state(200);
  this.data = $R.state([]);
  var y = $R(BarChart.y, this).bindTo(this.height, this.data);
  var x = $R(BarChart.x, this).bindTo(this.width, this.data);
}
BarChart.y = function (height, data) {
  return d3.scale.linear()
    .domain([0, d3.max(data, function(d) { return d.value })])
    .range([height, 0]);
}
BarChart.x = function (width, data) {
  return d3.scale.ordinal()
    .domain(d3.range(0, data.length))
    .rangeRoundBands([0, width], .1);
}