code: public void writeToGSEA(final Model model, OutputStream out) throws IOException
  	{
  		Collection<GMTEntry> entries = convert(model);
  		if (entries.size() > 0)
  		{
  			Writer writer = new OutputStreamWriter(out);
  			for (GMTEntry entry : entries) {
  				if ((minNumOfGenesPerEntry <= 1 && !entry.identifiers().isEmpty())
  						|| entry.identifiers().size() >= minNumOfGenesPerEntry)
  				{
  					writer.write(entry.toString() + "\n");
  				}
  			}
  			writer.flush();
  		}
  	}
docs: Converts model to GSEA (GMT) and writes to out.
  See class declaration for more information.
  
  @param model Model
  @param out output stream to write the result to
  @throws IOException when there's an output stream error