问用d3.js在一张图中叠加列图

EN

//x axis is ordinal
var x = d3.scale.ordinal()
    .rangeRoundBands([0, width-150], .1);
//y left axis is linear for head count
var y = d3.scale.linear()
    .rangeRound([height, 0]);
//this scale is for the average
y1 = d3.scale.linear().range([height, 0]).domain([0,100]);//marks can have min 0 and max 100
// y axis right for average marks.
var yAxisRight = d3.svg.axis().scale(y1)
    .orient("right").ticks(5); 

  //filter out name and average
  color.domain(d3.keys(data[0]).filter(function(key) { return key !== "Name" && key !=="Average"; }));
  data.forEach(function(d) {
    var y0 = 0;
    d.group = color.domain().map(function(name) { return {name: name, y0: y0, y1: y0 += +d[name]}; });
    d.total = d.group[d.group.length - 1].y1;
  });


  x.domain(data.map(function(d) { return d.Name; }));
  //stores toltal headcount
  y.domain([0, d3.max(data, function(d) { return d.total; })]);

  //line function for averageLine
  var averageline = d3.svg.line()
      .x(function(d) { return x(d.Name) + x.rangeBand()/2; })
      .y(function(d) { return y1(d.Average); });

  //this will make the y axis to the right
  svg.append("g")               
        .attr("class", "y axis")    
        .attr("transform", "translate(" + (width-100) + " ,0)") 
        .style("fill", "red")       
        .call(yAxisRight);

  svg.append("g")
      .attr("class", "x axis")
      .attr("transform", "translate(0," + height + ")")
      .call(xAxis);

  svg.append("g")
      .attr("class", "y axis")
      .call(yAxis)
    .append("text")
      .attr("transform", "rotate(-90)")
      .attr("y", 6)
      .attr("dy", ".71em")
      .style("text-anchor", "end")
      .text("Population");

  var state = svg.selectAll(".state")
      .data(data)
    .enter().append("g")
      .attr("class", "g")
      .attr("transform", function(d) { return "translate(" + x(d.Name) + ",0)"; });
  //adding the rect for group chart
  state.selectAll("rect")
      .data(function(d) { return d.group; })
    .enter().append("rect")
      .attr("width", x.rangeBand())
      .attr("y", function(d) { return y(d.y1); })
      .attr("height", function(d) { return y(d.y0) - y(d.y1); })
      .style("fill", function(d) { return color(d.name); });

  svg.append("path")        // Add the valueline path.
        .attr("d", averageline(data));
  //add the legend
  var legend = svg.selectAll(".legend")
      .data(color.domain().slice().reverse())
    .enter().append("g")
      .attr("class", "legend")
      .attr("transform", function(d, i) { return "translate(0," + i * 20 + ")"; });

  legend.append("rect")
      .attr("x", width - 18)
      .attr("width", 18)
      .attr("height", 18)
      .style("fill", color);

  legend.append("text")
      .attr("x", width - 24)
      .attr("y", 9)
      .attr("dy", ".35em")
      .style("text-anchor", "end")
      .text(function(d) { return d; });

var averageline = d3.svg.line()
      .x(function(d) { return x(d.Name) + x.rangeBand()/2; })
      .y(function(d) { return y1(d.Average); }).interpolate("basis");