anchor.diff:              
               for (var r=0; r<rows; r++) {
                   var caseId = dt.getValue(r,0);
  -                if (caseIdsFilter!=null && !caseIdsFilter[caseId]) continue;
  +                if (filter && !caseIdsFilter[caseId]) continue;
                   var v = dt.getValue(r,col);
                   if (v==null) continue;
                   var i=0;
  
positive.code:     };
      var csObs = new CaseSelectObserver();
      
      function nrKeys(a) {
          var i = 0;
          for (var key in a) i++;
          return i;
  
negative.code:         });
          google.visualization.events.addListener(chart, 'ready', function(e){
              csObs.subscribe(div.id,function(caseId) {
                  if (caseId==null) {
                      chart.setSelection();
                  } else if ((typeof caseId)==(typeof '')) {
                      var ix = hist[1][caseId];
                      chart.setSelection(ix==null?null:[{'row': ix}]);
                  } else if ((typeof caseId)==(typeof {})) {
  