code: def write_results(self,folder=None, filename='results.txt', to_file=True):
          
          if folder is None:
              folder = self.folder
          if to_file:
              fout = open(os.path.join(folder,filename), 'w')
          header = ''
          for m in self.popset.shortmodelnames:
              header += 'lhood_{0} L_{0} pr_{0} '.format(m)
          header += 'fpV fp FPP'
          if to_file:
              fout.write('{} \n'.format(header))
          Ls = {}
          Ltot = 0
          lhoods = {}
          for model in self.popset.modelnames:
              lhoods[model] = self.lhood(model)
              Ls[model] = self.prior(model)*lhoods[model]
              Ltot += Ls[model]
  
          line = ''
          for model in self.popset.modelnames:
              line += '%.2e %.2e %.2e ' % (lhoods[model], Ls[model], Ls[model]/Ltot)
          line += '%.3g %.3f %.2e' % (self.fpV(),self.priorfactors['fp_specific'],self.FPP())
  
          if to_file:
              fout.write(line+'\n')
              fout.close()
  
          return header, line
docs: Writes text file of calculation summary.
  
          :param folder: (optional)
              Folder to which to write ``results.txt``.
  
          :param filename:
              Filename to write.  Default=``results.txt``.
  
          :param to_file:
              If True, then writes file.  Otherwise just return header, line.
  
          :returns:
              Header string, line