  slv_define_parm(parameters, real_parm,	       "cnlow", "smallest allowable column norm", REX(1),
	       U_p_real(val, 0.01),U_p_real(lo, 0),U_p_real(hi,100000000.5), 3);
  SLV_RPARM_MACRO(CNLOW_PTR,parameters);
