docs: def hrd_new(self, input_label="", skip=0):
          """
          plot an HR diagram with options to skip the first N lines and
          add a label string
  
          Parameters
          ----------
          input_label : string, optional
              Diagram label.  The default is "".
          skip : integer, optional
              Skip the first n lines.  The default is 0.
  
          """
          xl_old=pyl.gca().get_xlim()
          if input_label == "":
              my_label="M="+str(self.header_attr['initial_mass'])+", Z="+str(self.header_attr['initial_z'])
          else:
              my_label="M="+str(self.header_attr['initial_mass'])+", Z="+str(self.header_attr['initial_z'])+"; "+str(input_label)
  
          pyl.plot(self.data[skip:,self.cols['log_Teff']-1],self.data[skip:,self.cols['log_L']-1],label = my_label)
          pyl.legend(loc=0)
          xl_new=pyl.gca().get_xlim()
          pyl.xlabel('log Teff')
          pyl.ylabel('log L')
          if any(array(xl_old)==0):
              pyl.gca().set_xlim(max(xl_new),min(xl_new))
          elif any(array(xl_new)==0):
              pyl.gca().set_xlim(max(xl_old),min(xl_old))
          else:
              pyl.gca().set_xlim([max(xl_old+xl_new),min(xl_old+xl_new)])