title: Initial Range selection in DC.js chart
body: <p>I would like to make an initial range selection in some dc.js charts (bar and line).<br>
  So I add this for example:</p>
  
  <pre><code>.filter([7,10])
  </code></pre>
  
  <p>And the range appears well on the chart, but apparently 0 observations are selected.<br>
  I expected a few thousands observations selected. Like it does when I select the range [7,10] manually with the brush.</p>
  
  <p>Any hint on what I'm missing here?</p>
  
  <p>Part of my code:</p>
  
  <pre><code>    var chart_globalscore = dc.barChart('#chart_globalscore');
  (...)
      var ndx = crossfilter(data_movies)
          ,all = ndx.groupAll()
  (...)
          ,GlobalScoreDimension = ndx.dimension(function(d) { if ( !isNaN(d.GlobalScore) ) {return Math.round(d.GlobalScore*10)/10 ;} else {return -1;} })
          ,GlobalScoreGroup = GlobalScoreDimension.group()
  (...)
          ;
  (...)
      chart_globalscore
          .width(width001)
          .height(height001)
          .margins(margins)
          .dimension(GlobalScoreDimension)
          .group(GlobalScoreGroup)
          .round(function(val){return Math.round(val*10)/10;})
          .x(d3.scale.linear().domain([0, 10.1]))
          .filter([7,10])
          .centerBar(false)
          .transitionDuration(transitionDuration)
          .elasticY(true)
          .gap(1)
          .xUnits(function(){return 100;})
          .renderHorizontalGridLines(true)
          .yAxis().ticks(2)
          ;
  </code></pre>