title: D3 Selecting an element inside an SVG
body: <p>I am trying to create some graphs in D3. So far love it, but I'm getting a bit stuck. 
  I want to create one area to hold the data points and another to hold the axis and labels. 
  I think I will go even more fine grained than that to make updating the graph more efficient. But the issue I am having is that I can't seem to select sub elements within the SVG. </p>
  
  <p>Here is what I have:</p>
  
  <pre><code>var graph = d3.select('#Graph svg')
  if (graph[0][0] == null){
      graph = d3.select('#Graph')
          .append("svg:svg")
          .attr("width",width)
          .attr("height",height)
          .attr("class","chart");
  }
  
  graph.append("svg:g")
      .attr("id","data")
  </code></pre>
  
  <p>Now I have not found a way to select that data container. I have tried</p>
  
  <pre><code>d3.select("#Graph svg data")
  </code></pre>
  
  <p>But no luck. Any Ideas?</p>