format_float_user = new char[n];

	strcpy(format_float_user,arg[iarg+2]);

      } else {

	int i = atoi(arg[iarg+1]);

	if (i < 1 || i > nfield_initial)

	int i = atoi(arg[iarg+1]) - 1;

	if (i < 0 || i >= nfield_initial)

	  error->all("Illegal thermo_modify command");

	if (format_user[i]) delete [] format_user[i];

	int n = strlen(arg[iarg+2]) + 1;

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

   allocate all per-field memory

   allow for addition of Volume field at run time

   allow each c_ID to imply 2 Compute objects (if it has id_pre)

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

void Thermo::allocate()

{

  // n = specified fields + Volume field (added at run time)

  int n = nfield_initial + 1;

  keyword = new char*[n];