title: Filter CSV rows to return a chart
body: <p>I'm struggling to get this code to work</p>
  
  <pre><code>var theBeeyatch = d3.csv("data/SalesDUMP.csv", function(csv) {
  
      csv = csv.filter(function(row) {
          return row['Year'] == '2012' || row['Month'] == '1';
      })
  });
  
  var Chart = d3.select("body")
      .append("svg")
      .attr("width", 400)
      .attr("height", 200)
  
      .selectAll("rect")
      .data(theBeeyatch)
      .enter().append("rect")
      .attr("x", function (d, i) {return i * 20 + 20;})
      .attr("y", 100)
      .attr("width", 20)
      .attr("height", function (d) {return d.Year;});
  </code></pre>
  
  <p>The CSV file looks like this</p>
  
  <pre><code>Year,Month,ProductClass,Sales
  2011,1,BA  ,28840
  2011,1,BH  ,2800
  2011,1,MB  ,1103200
  2012,1,BA  ,70680
  2012,1,MB  ,1596000
  2012,1,_OTH,1530
  2013,1,BA  ,120513.6
  2013,1,BH  ,17640
  2013,1,MB  ,1852761.6
  </code></pre>
  
  <p>I've tried filtering it as a string aswell. I have also tried parsing it as an integer. </p>
  
  <p>There is no error in the console, but nothing appears on screen. I've searched high and low but have found nothing that's helping me.</p>