title: highcharts heatmap large values
body: <p>I have a heatmap example in the folowing <a href="http://jsfiddle.net/1fj2o0j7/" rel="nofollow">link</a>. The example works perfectly as intended.
  The javascript is as follows:</p>
  
  <pre><code>$(function () {
  $('#chart').highcharts({
          chart: {'zoomType': 'x', 'panKey': 'shift', 'height': 350, 'panning': 'true', 'renderTo': 'chart', 'type': 'heatmap'},
          title: {'text': 'test1'},
  
          xAxis:{categories: ['0', '39', '43', '53', '594', '2138', '2793', '3163', '3450', '5548', '7338', '8238', '8484', '8768', '9890', '10164', '10805', '11136', '11238', '11246', '11260']
          },
  
          colorAxis: {
              min: 0,
              minColor: '#FFFFFF',
              maxColor: Highcharts.getOptions().colors[0]
          },
  
          legend: {
              align: 'right',
              layout: 'vertical',
              margin: 0,
              verticalAlign: 'top',
              y: 25,
              symbolHeight: 280
          },
          yAxis: {'categories': ['Plag. Conf.']},
          series: [{'dataLabels': {'color': '#000000'}, 'data': [[0, 0, 0.22442165397324812], [1, 0, 0.7752904636683974], [2, 0, 0.23883733197735627], [3, 0, 0.3482875869692335], [4, 0, 0.258070694541037], [5, 0, 0.47030915290735903], [6, 0, 0.3483451910956659], [7, 0, 0.4273295797570711], [8, 0, 0.42551220835600195], [9, 0, 0.17503429231614342], [10, 0, 0.400566592735601], [11, 0, 0.7072621636869421], [12, 0, 0.5863121178991313], [13, 0, 0.15765898852599733], [14, 0, 0.31159690000560425], [15, 0, 0.31414482011700673], [16, 0, 0.17269348665931927], [17, 0, 0.33469995479740144], [18, 0, 0.7833757398833074], [19, 0, 0.873319790409567], [20, 0, 0.24485995289730964]], 'name': 'test1', 'borderWidth': 1}],
          tooltip: {
              formatter: function () {
                  return '&lt;b&gt;Passage starting at ' + this.series.xAxis.categories[this.point.x] + '&lt;/b&gt; has &lt;br&gt;&lt;b&gt;' +
                      this.point.value + '&lt;/b&gt; for &lt;br&gt;&lt;b&gt;' + this.series.yAxis.categories[this.point.y] + '&lt;/b&gt;';
              }
          }
      });
  });
  </code></pre>
  
  <p>I have another example <a href="http://jsfiddle.net/sp4mg43t/" rel="nofollow">here</a> containing a large number of values that doesn't work as well as the first fiddle, even though both have been generated using the same program.</p>
  
  <p>What am I doing wrong?</p>