compute scaled kinetic energy tensor without destroying the original data

  // invoke temperature if it hasn't been already

  double *ke_tensor;

  double ke_tensor[6];

  if (keflag) {

    if (temperature->invoked_vector != update->ntimestep)

      temperature->compute_vector();

    ke_tensor = temperature->vector;

    for (int i = 0; i < 6; ++i)

      ke_tensor[i] = temperature->vector[i] / (*scale_grem);

  }

  for (int i = 0; i < 6; i++)

    ke_tensor[i] /= *scale_grem;

  if (dimension == 3) {

    inv_volume = 1.0 / (domain->xprd * domain->yprd * domain->zprd);