Overly complicated d3

gistfile1.txt

<script>
  var trans = [["2-21","129.68"],["2-22","92.79"],["2-23","196.22"],["2-24","187.71"],["2-25","16.47"],["2-26","18.5"],["2-27","110.48"],["2-28","122.61"],["2-29","114.11"],["3-01","121.74"],["3-02","267.23"],["3-03","167.61"],["3-04","10.26"],["3-05","46.32"],["3-06","40.76"],["3-07","309.39"],["3-08","71.91"],["3-09","246.11"],["3-10","148.21"],["3-11","10.01"],["3-12","118.58"],["3-13","109.69"],["3-14","125.81"],["3-15","116.23"],["3-16","201.83"],["3-17","64.68"],["3-19","44.28"],["3-20","118.25"],["3-21","365.65"],["3-22","216.62"]];
  var vans =  [["3-23","105.78"],["3-24","46.01"],["3-26","144.34"],["3-27","193.03"],["3-28","112.92"],["3-29","147.45"],["3-30","103.91"],["3-31","70.93"],["4-02","153.63"],["4-03","116.56"],["4-04","124.04"],["4-05","135.46"],["4-06","200.77"],["4-07","141.15"],["4-09","145.97"],["4-10","218.34"],["4-11","169.59"],["4-12","235.91"],["4-13","200.32"],["4-14","207.49"],["4-16","230.42"],["4-17","254.29"],["4-18","186.4"],["4-19","164.49"],["4-20","235.65"],["4-21","110.9"],["4-22","25.81"],["4-23","236.41"],["4-24","245.86"],["4-25","206.35"],["4-26","196.54"],["4-27","439.04"],["4-28","147.73"],["4-29","18.78"],["4-30","226.39"],["5-01","144.6"],["5-02","221.85"],["5-03","275.24"],["5-04","299.16"],["5-05","127.31"],["5-06","38.74"],["5-07","340.82"],["5-08","212.36"],["5-09","162.26"],["5-10","249.45"],["5-11","236.92"],["5-12","200.32"],["5-13","125.44"],["5-14","144.52"],["5-15","294.36"],["5-16","197.5"],["5-17","214.0"],["5-18","296.85"],["5-19","134.28"],["5-20","49.47"]];  
  
  $(function(){
  
     setInterval(function() {
        trans.shift();
        var cow = vans.shift();
        trans.push(cow);
        vans.push(cow)
        redraw();
      }, 1500);
  
    var w = 40,
        h = 600;
   
     var x = d3.scale.linear()
         .domain([0, 1])
         .range([0, w]);
   
     var y = d3.scale.linear()
         .domain([0, 400])
         .rangeRound([0, h]);
       
       
     var chart = d3.select("body").append("svg")
          .attr("class", "chart")
          .attr("width", w * trans.length - 1)
          .attr("height", h)
          .style("padding-bottom", '50px');

    // holder for rects
    body = chart.append("g")
      .attr("transform", "translate(0,0)");

    // holder for the second label 
    booty = chart.append("g")
      .attr("id", 'booty')
        
    body.selectAll("rect")
         .data(trans)
       .enter().append("rect")
         .attr("x", function(d, i) { return x(i) - .5; })
         .attr("y", function(d) { return h - y(d[1]) - .5; })
         .attr("width", w)
         .attr("height", function(d) { return y(d[1]); });        

    body.append("line")
          .attr("x1", 0)
          .attr("x2", w * trans.length)
          .attr("y1", h - .5)
          .attr("y2", h - .5)
          .style("stroke", "#000");      


      function redraw() {
        // rectangles
         var rect = body.selectAll("rect")
             .data(trans, function(d) { return d[0]; });
     
         rect.enter().insert("rect", "line")
             .attr("x", function(d, i) { return x(i + 1) - .5; })
             .attr("y", function(d) { return h - y(d[1]) - .5; })
             .attr("width", w)
             .attr("height", function(d) { return y(d[1]); })
           .transition()
             .duration(1000)
             .attr("x", function(d, i) { return x(i) - .5; });
     
         rect.transition()
             .duration(1000)
             .attr("x", function(d, i) { return x(i) - .5; });
     
         rect.exit().transition()
             .duration(1000)
             .attr("x", function(d, i) { return x(i - 1) - .5; })
             .remove();





      var text =  body.selectAll("text")
        .data(trans, function(d) { return d[0]; })
               
         text.enter().insert('text')
               .attr('x', function(d, i) { return x(i + 1) - .5; })
               .attr('y', function(d){return h - y(d[1]) - .5; })
               .attr('dx', 8)
               .attr("dy", "1.2em")
               .attr("text-anchor", 'start')
               .text(function(d, i){
                 return  Math.round(d[1]);
               });
               
           text.transition()
               .duration(1000)
               .attr("x", function(d, i){return x(i) - .5});
               
          text.exit().transition()
            .duration(1000)
            .attr("x", function(d, i) {return x(i - 1) - .5})
            .remove();
         

      bang = booty.selectAll("text")
        .data(trans, function(d) {return d[1];})
        
        bang.enter().append("text")
        .attr("text-anchor", 'start')
        .attr('x', function(d, i) { return x(i + 1) - .5; })
        .attr('y', 605)
        .attr("dx", 4)
        .attr('dy', '.71em')
        .text(function(d){ 
          return d[0];
        });

        bang.transition()
            .duration(1000)
            .attr("x", function(d, i){return x(i) - .5});
            
        bang.exit().transition()
            .duration(1000)
            .attr("x", function(d, i) {return y(i - 1) - .5})
            .remove();
        

       } // closes redraw        
       
    }); // document ready
        
        
</script>