Bar Chart And Line Chart

by Nivaldo

HTML

<div class="section system-efficiency">
</div>

CSS

.axis path,
.axis line{
    fill: none;
    stroke: black;
    stroke-width: 2;
}

path.line{
    fill: none;
    stroke: firebrick;
    stroke-width: 2;
}

.air_used {
  fill: steelblue;
}

JavaScript

var data = [
  {
    "air_used": 0.342706, 
    "datestr": "2012-12-01 00:00:00", 
    "energy_used": 0.106402
  }, 
  {
    "air_used": 0.400776, 
    "datestr": "2013-01-01 00:00:00", 
    "energy_used": 0.250462
  }, 
  {
    "air_used": 0.103541, 
    "datestr": "2013-02-01 00:00:00", 
    "energy_used": 0.040582
  }, 
  {
    "air_used": 0.97719, 
    "datestr": "2013-03-01 00:00:00", 
    "energy_used": 0.923212
  }, 
  {
    "air_used": 0.241088, 
    "datestr": "2013-04-01 00:00:00", 
    "energy_used": 0.20381
  }
];

// Margins, width and height. 
var margin = {top: 20, right: 20, bottom: 30, left: 10},
    body_width = parseInt(d3.select('body').style('width').replace('px','')),
    width = body_width - margin.left - margin.right,
    height = 200 - margin.top - margin.bottom;

// Width of bars, without padding. 
var barRawWidth = width / (data.length + 2);
var barPadding = 10;
var xStart = barPadding + (barRawWidth/2);
var barWidth = barRawWidth - (barPadding*2);

// Scales.
var x = d3.time.scale().range([xStart, width-xStart]);
var y = d3.scale.linear().range([height, 0]);

// Construct our SVG object.
var svg = d3.select(".system-efficiency").append("svg")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
  .append("g")
    .attr("transform", "translate(" + margin.left + "," + margin.top + ")");

// X-axis.
var xAxis = d3.svg.axis()
    .scale(x)
    .orient("bottom")
    .ticks(d3.time.month, 1)
    .tickFormat(d3.time.format('%b %Y'));
svg.append("g")
    .attr("class", "x axis")
    .attr("transform", "translate(0," + height + ")")
    //.call(xAxis);

// Date parsing.
var parseDate = d3.time.format("%Y-%m-%d %H:%M:%S");
data.forEach(function(d) {
  d.date = parseDate.parse(d.datestr);
});

// Set scale domains. 
var xExtent = d3.extent(data, function(d) { return d.date; });
var nxExtent = [d3.time.day.offset(xExtent[0], -20), d3.time.day.offset(xExtent[1],...