JQPlot Capture Click Event

JQPlot Capture Click Event

HTML

<script src="http://cdn.jsdelivr.net/jqplot/1.0.8/jquery.jqplot.min.js"></script>
<link rel="stylesheet" href="http://cdn.jsdelivr.net/jqplot/1.0.8/jquery.jqplot.min.css">
<script src="http://cdn.jsdelivr.net/jqplot/1.0.8/plugins/jqplot.canvasAxisTickRenderer.min.js"></script>
<script src="http://cdn.jsdelivr.net/jqplot/1.0.8/plugins/jqplot.categoryAxisRenderer.min.js"></script>
<script src="http://cdn.jsdelivr.net/jqplot/1.0.8/plugins/jqplot.barRenderer.min.js"></script>
<script src="http://cdn.jsdelivr.net/jqplot/1.0.8/plugins/jqplot.canvasTextRenderer.min.js"></script>
<script src="http://cdn.jsdelivr.net/jqplot/1.0.8/plugins/jqplot.pointLabels.min.js"></script>
<script src="http://cdn.jsdelivr.net/jqplot/1.0.8/plugins/jqplot.canvasAxisLabelRenderer.min.js"></script>
<script src="http://cdn.jsdelivr.net/jqplot/1.0.8/plugins/jqplot.canvasOverlay.js"></script>
<div id="label"></div>
<br/>
<div id="graph" style="height: 400px; width: 700px;"></div>

JavaScript

Array.prototype.average=function(){
    var sum=0;
    var j=0;
    for(var i=0;i<this.length;i++){
        if(isFinite(this[i])){
          sum=sum+parseFloat(this[i]);
           j++;
        }
    }
    if(j===0){
        return 0;
    }else{
        return sum/j;
    }
}
 
Array.prototype.stddev=function(){
    var n = 0;
    var sum = 0.0;
    var sum_sq = 0.0;
    for(var i=0;i<this.length;i++){
        n++;
        sum += this[i];
        sum_sq += this[i]*this[i];
    }
    return Math.sqrt( (sum_sq /n) - Math.pow(sum /n, 2));    
}

Array.prototype.average_t=function(){
    var sum=0;
    var j=0;
    var average_t = [];
    for(var i=0;i<this.length;i++){
        if(isFinite(this[i])){
          sum=sum+parseFloat(this[i]);
          j++;
          average_t[i] = sum/j
        }
    }
    if(j===0){
        return 0;
    }else{
        return average_t;
    }
}

function arrayColumn(arr, n) {
  return arr.map(x=> x[n]);
}

$(document).ready(function(){ 
var s3 = [['one', 2], ['two', 15], ['three', 1]];
var line = s3;
var firstcolumnArray = arrayColumn(s3, 0)
var options= {    
   title: 'Statistics on a Bar Chart',      
   series:[{
      renderer: $.jqplot.BarRenderer,                 
      rendererOptions: {          
         barMargin: 5,           
         fillToZero: true               
      },
      pointLabels: {
         show: true,
         formatString: '%.1f',
         seriesLabelIndex:1,
         hideZeros:false
      }
   }],
   axes: {      
      xaxis: {          
         tickRenderer: $.jqplot.CanvasAxisTickRenderer,
         renderer: $.jqplot.CategoryAxisRenderer,
         label: 'X Label'
      },      
      yaxis: {   
         labelRenderer: $.jqplot.CanvasAxisLabelRenderer,
         padMin: 0,
         pad: 1.1,
         label: 'Y Label',
         rendererOptions: { forceTickAt0: true}
      } 
   },    
   negativeSeriesColors:['darkred'],   
   grid:{
      background: '#f8f8f8'
   },   
   canvasOverlay: {
      show:...