title: vertices' attributes are not written to file when using igraph package in R
body: <p>I am using igraph in R to calculate some network centrality measures. Once the measures are ready, I want to write the graph into a file (say Pajek format) </p>
  
  <pre><code>V(net)$deg_net &lt;- degree(net, loops = F)
  V(net)$cls_net &lt;- closeness(net)
  </code></pre>
  
  <p>now the network "net" looks like this"</p>
  
  <pre><code>&gt;net
  IGRAPH UNW 80000 240000 --
  + attr: name (v/c), deg_net (v/n), cls_net (v/n), weight (e/n)
  + edges (vertex names):
  .
  .
  .
  </code></pre>
  
  <p>When I use </p>
  
  <pre><code>write.graph(net, "team_measures.txt", "pajek")
  </code></pre>
  
  <p>the final text file doesn't seem to include any information about the vertices, including their attributes (degree and closeness measures). It just is:</p>
  
  <p>*Vertices 80000</p>
  
  <p>*Edges </p>
  
  <p>1 1555 1</p>
  
  <p>1 6153 1 </p>
  
  <p>1 785 1</p>
  
  <p>and so on. Am I doing something wrong? </p>
  
  <p>I should also mention that "net" is a one-mode projection of a bipartite network. </p>