sualization');
  var options = {
    // option groupOrder can be a property name or a sort function
    // the sort function must compare two groups and return a value
    //     > 0 when a > b
    //     < 0 when a < b
    //       0 when a == b
    groupOrder: function (a, b) {
      return a.value - b.value;
    },
    groupOrderSwap: function (a, b, groups) {
    	var v = a.value;
    	a.value = b.value;
    	b.value = v;
    },
    groupTemplate: function(group){
      var container = document.createEl