anchor.diff:          });
           caseSelect.change(function(e) {
               var caseId = $('#case-select  option:selected').attr('value');
  -            csObs.fireSelection(caseId,'case-select')
  +            if (caseId=="") caseId=null;
  +            csObs.fireSelection(caseId,'case-select');
           });
       }
       
  
positive.code:         if (dt) {
              var headerMap = getHeaderMap(dt);
              var caseMap = getCaseMap(dt);
              
              plotAgeHistogram(dt,headerMap['age_at_diagnosis'],'age-hist');
              plotPieChart(dt,headerMap['histology'],'hist-pie');
              plotPieChart(dt,headerMap['2009stagegroup'],'stage-pie');
              plotPieChart(dt,headerMap['tumor_grade'],'grade-pie');
              
              var formatter = new google.visualization.PatternFormat(formatPatientLink('{0}'));
              formatter.format(dt, [0]);
              drawDataTable(dt,'clinical-data-table');
              
              var colCna = headerMap['copy_number_altered_fraction'];
              var colMut = headerMap['mutation_count'];
              plotMutVsCna(dt,colCna,colMut,caseMap,true,'scatter-plot');
          }
      }
      
      function drawDataTable(dt,divId) {
              var tableDataView = new google.visualization.DataView(dt);
              var table = new google.visualization.Table(document.getElementById(divId));
              var options = {
  
negative.code:         }
          return ix;
      }
   
      function plotHistogram(divId,dt,col,bins,hAxisTitle) {
          var div = document.getElementById(divId);
          if (col==null) {
              $(div).html("<font color='red'><b>No data<b></font>");
              return;
          }
          var hist = calcHistogram(dt,col,bins);
          var ageHistDTW = new DataTableWrapper();
          ageHistDTW.setDataMap(hist,['Age','# patients']);
          var column = new google.visualization.ColumnChart(div);
          var options = {
              hAxis: {title: hAxisTitle},
              vAxis: {title: '# of Patients'},
              legend: {position: 'none'}
          }
          column.draw(ageHistDTW.dataTable,options);
      }
      
      function plotPieChart(divId,dt,col) {
          var div = document.getElementById(divId);
          if (col==null) {
              $(div).html("<font color='red'><b>No data<b></font>");
              return;
          }
          var hist = calcHistogram(dt,col);
          var histHistDTW = new DataTableWrapper();
          histHistDTW.setDataMap(hist,[dt.getColumnLabel(col),'# patients']);
          var column = new google.visualization.PieChart(div);
          column.draw(histHistDTW.dataTable);
      }
      
  