use a hard error instead of changing settings without updating the underlying...

void BondOxdnaFene::init_style()

{

  /* special bonds have to be lj = 0 1 1 and coul = 1 1 1 to exclude

     the ss excluded volume interaction between nearest neighbors   */

  force->special_lj[1] = 0.0;

  force->special_lj[2] = 1.0;

  force->special_lj[3] = 1.0;

  force->special_coul[1] = 1.0;

  force->special_coul[2] = 1.0;

  force->special_coul[3] = 1.0;

  fprintf(screen,"Finding 1-2 1-3 1-4 neighbors ...\n"

                 " Special bond factors lj:   %-10g %-10g %-10g\n"

                 " Special bond factors coul: %-10g %-10g %-10g\n",

                 force->special_lj[1],force->special_lj[2],force->special_lj[3],

                 force->special_coul[1],force->special_coul[2],force->special_coul[3]);

  if (force->special_lj[1] != 0.0 || force->special_lj[2] != 1.0 || force->special_lj[3] != 1.0 ||

      force->special_coul[1] != 1.0 || force->special_coul[2] != 1.0 || force->special_coul[3] != 1.0)

  {

    if (comm->me == 0)

      error->warning(FLERR,"Use special bonds lj = 0,1,1 and coul = 1,1,1 with bond style oxdna/fene");

  }

    error->all(FLERR,"Must use 'special_bonds lj 0 1 1 coul 1 1 1' with bond style oxdna/fene");

}

/* ---------------------------------------------------------------------- */