title: how to access data from nested json array D3
body: <p>I have a JSON array like this:</p>
  
  <pre><code>{
  
    "nodes":[
  
             {"id":"x", "style":[
               {"shape":"circle","value":"10","fill":"red"}]
             },
             ....
             ....
             ],
  "links":[
  
           {"source":"x", "target":"y"},
           ....
           ....
  
         ]
  }
  </code></pre>
  
  <p>I want to fetch data from "style" field.
  It doesn't work if u write code like this</p>
  
  <pre><code>var node = svg.append("g")
      .attr("class", "nodes")    
      .selectAll("g")    
      .data(graph.nodes)    
      .enter().append("g")    
      .attr("fill",function(d){return(d.style.fill) })
  </code></pre>
  
  <p>how can I do?</p>