title: Highcharts shared tooltip requires different valueSuffix and varying decimals
body: <p>I have a Highchart Graph that plots Temperature, Wind, Pressure and Rainfall.</p>
  
  <p>It can be seen here <a href="http://www.dmjsystems.co.uk/weather/forecast.php" rel="noreferrer">http://www.dmjsystems.co.uk/weather/forecast.php</a></p>
  
  <p>I am using a shared Tooltip with the added complication that the Max Rain is a total of the min and the max in the stacked column for rain. Currently the code ignores my series based suffix and I have not been able to get individual decimals to work (i.e.they all show 3 decimal places).</p>
  
  <p>Each of the Items has a different suffix (Temp = (Degree sign)C, Wind = mph, Pressure = mb and Rain = in) and different numbers of decimal places (Wind = none, Temp = 1, Pressure = 1 and Rain = 3).</p>
  
  <p>I am currently using a general Tooltip coded as follows :</p>
  
  <pre><code>    tooltip: { shared : true,
              formatter: function() {
              return '&lt;span style="color:#039;font-weight:bold"&gt;' + Highcharts.dateFormat('%A' + ', ' + '%b %d' + ', ' + '%H' + ':' + '00',this.x) + '&lt;/span&gt;&lt;br/&gt;' +
                         this.points.map(function(point, idx) {
                             return '&lt;span style="color:' + point.series.color + '"&gt;' + point.series.name +
                                    '&lt;/span&gt;: &lt;span style="color:#669;font-weight:bold"&gt;' +
                                    Highcharts.numberFormat((idx == 0) ? point.total : point.y,3) +
                                    '&lt;/span&gt;';
                         }).join('&lt;br/&gt;');
              }
      },
  </code></pre>
  
  <p>but I think I need to move this (apart from shared : true) to series based tooltips that use pointFormat (especially tooltip.ySuffix which I think will let me specify the suffix correctly) and valueDecimals to set the decimal point for each series, but I cannot find any examples of code to use these functions.</p>
  
  <p>Also as soon as I move away from the general tooltip I cannot get the totalling to work for the stacked column.</p>
  
  <p>If anyone could point me in right direction I would appreciate it.</p>