title: R sankey plot node limit?
body: <p>Is there a node limit to sankey plots? I am trying to create a plot with a lot of nodes and the following code fails to produce a plot (but gives me no error warning).</p>
  
  <p>Any idea what is happening here?</p>
  
  <pre><code># sankey chart using d3 plugin for rCharts and the igraph library
  
  require(rCharts)
  require(igraph)
  
  # these are our vertices/nodes/end points/stages/categories/classes/whatever
  nodes = c(1:36)
  
  # the chart is basically a graph
  
  pairs=c()
  for (j in seq(1,36,by=4)) pairs=c(pairs,j,j+1,j+1,j+2,j+2,j+3)
  pairs
  g &lt;- graph(pairs)
  plot(g)
  E(g)
  E(g)$weights &lt;- rep(c(16667,500,100),9)
  length(E(g)$weights)
  
  # convert to data frame with appropriate node names
  edgelist &lt;- get.data.frame(g)
  
  # name columns as what is expected by plugin
  colnames(edgelist) &lt;- c("source", "target", "value")
  edgelist
  
  edgelist$source &lt;- lapply(edgelist$source, FUN = function(x) {nodes[x]})
  edgelist$target &lt;- lapply(edgelist$target, FUN = function(x) {nodes[x]})
  edgelist
  
  # now we plot
  sankeyPlot &lt;- rCharts$new()
  sankeyPlot$setLib('http://timelyportfolio.github.io/rCharts_d3_sankey/libraries/widgets/d3_sankey')
  sankeyPlot$set(
  data = edgelist,
  nodeWidth = 15,
  nodePadding = 15,
  layout = 32,
  width = 960,
  height = 500
  )
  sankeyPlot
  </code></pre>