title: How to update the map scale on crossfilter dimension.filter()?
body: <p>I'm working on a dashboard builded with d3, dc and crossfilter.
  the dataset is a tsv like this:<br>
  ID    type    val<br>
  1    pop    10000<br>
  1    var    100<br>
  2    pop    15000<br>
  2    var    -500<br>
  etc...<br></p>
  
  <p>the first dimension I make is on "type" column and I filter it to use only I indicator type. In this case the absolute value of population "pop" per municipality<br>
  than using dc.js I make a map (with scale.threshold or scale.quantize) and some chart with the dataset filtered in this way.</p>
  
  <p>I also have a button that allow to change the "type" filter to use the other indicator in the dataset. In this example "var" is the number of new resident in a municipality. <br>
  this is the code that update the dimension.filter on button click:</p>
  
  <pre><code>$(settings.container + " &gt; button").click(function() {
        //change the active state of the button
        $(settings.container + " &gt; button").removeClass('active');
        $(this).addClass('active');
  
        //get the name of the indicator type to be filtered from the data-filter button attribute
        var val = $(this).attr('data-filter');
  
  
        if(val){// if data-filter exist -&gt; filter the crossfilter dimension
            prinDashboard.dim[settings.dim.dim].filter(val);
        }else{// else filterAll
            prinDashboard.dim[settings.dim.dim].filterAll();
        }
  
        //redraw all the dc chart and mapp
        dc.redrawAll();
    })
  </code></pre>
  
  <p>dc.js take care of all the map and chart updating and all work fine but the map scale doesn't update to fit the new dataset. <br>
  for example if I initially define a scale.quantize that output these 5 brakes:0-5000, 5000-1000, 10000-15000, 15000-20000, 20000-25000 When I update the dataset the "var" values are also fitted in these brakes that are now meaningless.<br>
  What I want is to be able to rebuild the scale with the new dataset and than update the map.<br>
  Is there any way to do this in dc? or how can I "hack" what dc does using plain d3?</p>
  
  <p>I'll really appreciate any idea!</p>
  
  <p>Thanks</p>