cloudbox.cc

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/* Copyright (C) 2002-2012 Claudia Emde <claudia.emde@dlr.de>
                      
   This program is free software; you can redistribute it and/or modify it
   under the terms of the GNU General Public License as published by the
   Free Software Foundation; either version 2, or (at your option) any
   later version.
 
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
 
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
   USA. 
*/
 
#include "cloudbox.h"
 
extern const Index GFIELD3_P_GRID;
extern const Index GFIELD3_LAT_GRID;
extern const Index GFIELD3_LON_GRID;
 
/*===========================================================================
  === External declarations
  ===========================================================================*/
#include <algorithm>
#include <cmath>
#include <ctime>
#include <limits>
#include <stdexcept>
 
#include "arts.h"
#include "check_input.h"
#include "lin_alg.h"
#include "logic.h"
#include "math_funcs.h"
#include "mc_antenna.h"
#include "messages.h"
#include "physics_funcs.h"
#include "ppath.h"
#include "rng.h"
#include "sorting.h"
 
 
void chk_pnd_data(const GriddedField3& pnd_field_raw,
                  const String& pnd_field_file,
                  const Index& atmosphere_dim,
                  const Verbosity& verbosity) {
  CREATE_OUT3;
 
  const Vector& pfr_lat_grid =
      pnd_field_raw.get_numeric_grid(GFIELD3_LAT_GRID);
  const Vector& pfr_lon_grid =
      pnd_field_raw.get_numeric_grid(GFIELD3_LON_GRID);
 
  // The consistency of the dimensions is checked in the reading routine.
  // Here we have to check whether the atmospheric dimension is correct and whether
  // the particle number density is 0 on the cloudbox boundary and outside the cloudbox.
 
  out3 << "Check particle number density file " << pnd_field_file << "\n";
 
  if (atmosphere_dim == 1 &&
      (pfr_lat_grid.nelem() != 1 || pfr_lon_grid.nelem() != 1)) {
    ostringstream os;
    os << "The atmospheric dimension is 1D but the particle "
       << "number density file * " << pnd_field_file
       << " is for a 3D atmosphere. \n";
    throw runtime_error(os.str());
  }
 
  else if (atmosphere_dim == 3) {
    if (pfr_lat_grid.nelem() == 1 || pfr_lon_grid.nelem() == 1) {
      ostringstream os;
      os << "The atmospheric dimension is 3D but the particle "
         << "number density file * " << pnd_field_file
         << " is for a 1D or a 2D atmosphere. \n";
      throw runtime_error(os.str());
    }
  }
 
  out3 << "Particle number density data is o.k. \n";
}
 
 
void chk_pnd_raw_data(const ArrayOfGriddedField3& pnd_field_raw,
                      const String& pnd_field_file,
                      const Index& atmosphere_dim,
                      const Verbosity& verbosity) {
  CREATE_OUT3;
 
  for (Index i = 0; i < pnd_field_raw.nelem(); i++) {
    out3 << "Element in pnd_field_raw_file:" << i << "\n";
    chk_pnd_data(pnd_field_raw[i], pnd_field_file, atmosphere_dim, verbosity);
  }
}
 
 
void chk_pnd_field_raw_only_in_cloudbox(
    const Index& dim,
    const ArrayOfGriddedField3& pnd_field_raw,
    ConstVectorView p_grid,
    ConstVectorView lat_grid,
    ConstVectorView lon_grid,
    const ArrayOfIndex& cloudbox_limits) {
  Numeric p, lat, lon, v;
  Index n, p_i, lat_i, lon_i;
  // For any non-zero point, verify we're outside the cloudbox
  for (n = 0; n < pnd_field_raw.nelem(); n++) {
    for (p_i = 0; p_i < pnd_field_raw[n].data.npages(); p_i++) {
      for (lat_i = 0; lat_i < pnd_field_raw[n].data.nrows(); lat_i++) {
        for (lon_i = 0; lon_i < pnd_field_raw[n].data.ncols(); lon_i++) {
          v = pnd_field_raw[n].data(p_i, lat_i, lon_i);
          if (v != 0) {
            // Verify pressure is between cloudbox limits
            p = pnd_field_raw[n].get_numeric_grid(GFIELD3_P_GRID)[p_i];
            //                        if (!((p <= p_grid[cloudbox_limits[0]]) &
            //                              (p >= p_grid[cloudbox_limits[1]]))) {
            if ((p <= p_grid[cloudbox_limits[1]]) ||
                ((p >= p_grid[cloudbox_limits[0]]) &&
                 (cloudbox_limits[0] != 0))) {
              ostringstream os;
              os << "Found non-zero pnd outside cloudbox. "
                 << "Cloudbox extends from p=" << p_grid[cloudbox_limits[0]]
                 << " Pa to p=" << p_grid[cloudbox_limits[1]]
                 << " Pa, but found pnd=" << v << "/m³ at p=" << p
                 << " Pa for scattering "
                 << "element #" << n << ".";
              throw runtime_error(os.str());
            }
            // Verify latitude is too
            if (dim > 1) {
              lat = pnd_field_raw[n].get_numeric_grid(GFIELD3_LAT_GRID)[lat_i];
              if (!((lat > lat_grid[cloudbox_limits[2]]) bitand
                    (lat < lat_grid[cloudbox_limits[3]]))) {
                ostringstream os;
                os << "Found non-zero pnd outside cloudbox. "
                   << "Cloudbox extends from lat="
                   << lat_grid[cloudbox_limits[2]]
                   << "° to lat=" << lat_grid[cloudbox_limits[3]]
                   << "°, but found pnd=" << v << "/m³ at lat=" << lat
                   << "° for scattering "
                   << "element #" << n << ".";
                throw runtime_error(os.str());
              }
            }
            // Etc. for longitude
            if (dim > 2) {
              lon = pnd_field_raw[n].get_numeric_grid(GFIELD3_LON_GRID)[lon_i];
              if (!((lon > lon_grid[cloudbox_limits[4]]) bitand
                    (lon < lon_grid[cloudbox_limits[5]]))) {
                ostringstream os;
                os << "Found non-zero pnd outside cloudbox. "
                   << "Cloudbox extends from lon="
                   << lon_grid[cloudbox_limits[4]]
                   << "° to lat=" << lon_grid[cloudbox_limits[5]]
                   << "°, but found pnd=" << v << "/m³ at lon=" << lon
                   << "° for scattering "
                   << "element #" << n << ".";
                throw runtime_error(os.str());
              }
            }
          }
        }
      }
    }
  }
}
 
 
void chk_scat_species(const ArrayOfString& scat_species, const String& delim) {
  ArrayOfString strarr;
  Index nelem = 2;
 
  for (Index k = 0; k < scat_species.nelem(); k++) {
    scat_species[k].split(strarr, delim);
    if (strarr.nelem() < nelem) {
      ostringstream os;
      os << "Individual strings in scat_species must contain at least " << nelem
         << " elements,\n"
         << "but entry #" << k << " contains only the following "
         << strarr.nelem() << ":\n"
         << strarr << "\n";
      throw runtime_error(os.str());
    }
  }
}
 
 
void chk_scattering_data(const ArrayOfSingleScatteringData& scat_data,
                         const ArrayOfScatteringMetaData& scat_meta,
                         const Verbosity&) {
  if (scat_data.nelem() != scat_meta.nelem()) {
    ostringstream os;
    os << "The number of elements in in current scat_species'  *scat_data* and "
       << "*scat_meta* do not match.\n"
       << "Each *scat_data* entry must correspond to one entry in *scat_meta*.";
    throw runtime_error(os.str());
  }
}
 
 
void chk_scattering_meta_data(const ScatteringMetaData& scat_meta_single _U_,
                              const String& scat_meta_file,
                              const Verbosity& verbosity) {
  CREATE_OUT3;
  out3 << "  Check scattering meta data file " << scat_meta_file << "\n";
 
  /* this check is outdated. type now is free from!
   however, we might want to have other things checked here!?
   - which parameters at least are needed? -> radius, ...?
   - ...
  if  (scat_meta_single.type != "Ice" && scat_meta_single.type != "Water" && scat_meta_single.type != "Aerosol")
  {
          ostringstream os; 
          os << "Type in " << scat_meta_file << " must be 'Ice', 'Water' or 'Aerosol'\n";     
          throw runtime_error( os.str() );
        }
*/
  //(more) checks need to be included
}
 
 
void chk_scat_data(const SingleScatteringData& scat_data_single,
                   const Verbosity& verbosity) {
  CREATE_OUT3;
 
  assert(scat_data_single.ptype == PTYPE_GENERAL ||
         scat_data_single.ptype == PTYPE_TOTAL_RND ||
         scat_data_single.ptype == PTYPE_AZIMUTH_RND);
 
  if (scat_data_single.za_grid[0] != 0.) {
    ostringstream os;
    os << "The first value of the zenith angle grid in the single"
       << " scattering properties data must be 0.";
    throw runtime_error(os.str());
  }
 
  if (last(scat_data_single.za_grid) != 180.) {
    ostringstream os;
    os << "The last value of the zenith angle grid in the single"
       << " scattering properties data must be 180.";
    throw runtime_error(os.str());
  }
 
  if (scat_data_single.ptype == PTYPE_GENERAL &&
      scat_data_single.aa_grid[0] != -180.) {
    ostringstream os;
    os << "For ptype = \"general\" the first value"
       << " of the azimuth angle grid in the single scattering"
       << " properties data must be -180.";
    throw runtime_error(os.str());
  }
 
  if (scat_data_single.ptype == PTYPE_AZIMUTH_RND &&
      scat_data_single.aa_grid[0] != 0.) {
    ostringstream os;
    os << "For ptype = \"azimuthally_random\""
       << " the first value"
       << " of the azimuth angle grid in the single scattering"
       << " properties data must be 0.";
    throw runtime_error(os.str());
  }
 
  if (scat_data_single.ptype != PTYPE_TOTAL_RND &&
      last(scat_data_single.aa_grid) != 180.) {
    ostringstream os;
    os << "For ptypes = \"azimuthally_random\" and \"general\""
       << " the last value of the azimuth angle grid in the single"
       << " scattering properties data must be 180.";
    throw runtime_error(os.str());
  }
 
  ostringstream os_pha_mat;
  os_pha_mat << "pha_mat ";
  ostringstream os_ext_mat;
  os_ext_mat << "ext_mat ";
  ostringstream os_abs_vec;
  os_abs_vec << "abs_vec ";
 
  switch (scat_data_single.ptype) {
    case PTYPE_GENERAL:
 
      out3 << "  Data is for arbitrarily orientated particles. \n";
 
      chk_size(os_pha_mat.str(),
               scat_data_single.pha_mat_data,
               scat_data_single.f_grid.nelem(),
               scat_data_single.T_grid.nelem(),
               scat_data_single.za_grid.nelem(),
               scat_data_single.aa_grid.nelem(),
               scat_data_single.za_grid.nelem(),
               scat_data_single.aa_grid.nelem(),
               16);
 
      chk_size(os_ext_mat.str(),
               scat_data_single.ext_mat_data,
               scat_data_single.f_grid.nelem(),
               scat_data_single.T_grid.nelem(),
               scat_data_single.za_grid.nelem(),
               scat_data_single.aa_grid.nelem(),
               7);
 
      chk_size(os_abs_vec.str(),
               scat_data_single.abs_vec_data,
               scat_data_single.f_grid.nelem(),
               scat_data_single.T_grid.nelem(),
               scat_data_single.za_grid.nelem(),
               scat_data_single.aa_grid.nelem(),
               4);
      break;
 
    case PTYPE_TOTAL_RND:
 
      out3 << "  Data is for macroscopically isotropic and mirror-symmetric "
           << "scattering media, i.e. for totally randomly oriented particles "
           << "with at least one plane of symmetry. \n";
 
      chk_size(os_pha_mat.str(),
               scat_data_single.pha_mat_data,
               scat_data_single.f_grid.nelem(),
               scat_data_single.T_grid.nelem(),
               scat_data_single.za_grid.nelem(),
               1,
               1,
               1,
               6);
 
      chk_size(os_ext_mat.str(),
               scat_data_single.ext_mat_data,
               scat_data_single.f_grid.nelem(),
               scat_data_single.T_grid.nelem(),
               1,
               1,
               1);
 
      chk_size(os_abs_vec.str(),
               scat_data_single.abs_vec_data,
               scat_data_single.f_grid.nelem(),
               scat_data_single.T_grid.nelem(),
               1,
               1,
               1);
      break;
 
    case PTYPE_AZIMUTH_RND:
 
      out3 << "  Data is for azimuthally randomly oriented particles. \n";
 
      chk_size(os_pha_mat.str(),
               scat_data_single.pha_mat_data,
               scat_data_single.f_grid.nelem(),
               scat_data_single.T_grid.nelem(),
               scat_data_single.za_grid.nelem(),
               scat_data_single.aa_grid.nelem(),
               scat_data_single.za_grid.nelem(),
               1,
               16);
 
      chk_size(os_ext_mat.str(),
               scat_data_single.ext_mat_data,
               scat_data_single.f_grid.nelem(),
               scat_data_single.T_grid.nelem(),
               scat_data_single.za_grid.nelem(),
               1,
               3);
 
      chk_size(os_abs_vec.str(),
               scat_data_single.abs_vec_data,
               scat_data_single.f_grid.nelem(),
               scat_data_single.T_grid.nelem(),
               scat_data_single.za_grid.nelem(),
               1,
               2);
      break;
  }
 
  // Here we only check whether the temperature grid is of the unit K, not
  // whether it corresponds to the required values in t_field. The second
  // option is not trivial since here one has to look whether the pnd_field
  // is non-zero for the corresponding temperature. This check is done in the
  // functions where the multiplication with the particle number density is
  // done.
  if (scat_data_single.T_grid[0] < 0. ||
      last(scat_data_single.T_grid) > 1001.) {
    ostringstream os;
    os << "The temperature values in the single scattering data"
       << " are negative or very large. Check whether you use the "
       << "right unit [Kelvin].";
    throw runtime_error(os.str());
  }
}
 
bool is_gp_inside_cloudbox(const GridPos& gp_p,
                           const GridPos& gp_lat,
                           const GridPos& gp_lon,
                           const ArrayOfIndex& cloudbox_limits,
                           const bool& include_boundaries,
                           const Index& atmosphere_dim)
 
{
  if (include_boundaries) {
    // Pressure dimension
    double ipos = fractional_gp(gp_p);
    if (ipos < double(cloudbox_limits[0]) ||
        ipos > double(cloudbox_limits[1])) {
      return false;
    }
 
    else if (atmosphere_dim >= 2) {
      // Latitude dimension
      ipos = fractional_gp(gp_lat);
      if (ipos < double(cloudbox_limits[2]) ||
          ipos > double(cloudbox_limits[3])) {
        return false;
      }
 
      else if (atmosphere_dim == 3) {
        // Longitude dimension
        ipos = fractional_gp(gp_lon);
        if (ipos < double(cloudbox_limits[4]) ||
            ipos > double(cloudbox_limits[5])) {
          return false;
        }
      }
    }
    return true;
  } else {
    // Pressure dimension
    double ipos = fractional_gp(gp_p);
    if (ipos <= double(cloudbox_limits[0]) ||
        ipos >= double(cloudbox_limits[1])) {
      return false;
    }
 
    else if (atmosphere_dim >= 2) {
      // Latitude dimension
      ipos = fractional_gp(gp_lat);
      if (ipos <= double(cloudbox_limits[2]) ||
          ipos >= double(cloudbox_limits[3])) {
        return false;
      }
 
      else if (atmosphere_dim == 3) {
        // Longitude dimension
        ipos = fractional_gp(gp_lon);
        if (ipos <= double(cloudbox_limits[4]) ||
            ipos >= double(cloudbox_limits[5])) {
          return false;
        }
      }
    }
    return true;
  }
}
 
bool is_inside_cloudbox(const Ppath& ppath_step,
                        const ArrayOfIndex& cloudbox_limits,
                        const bool include_boundaries)
 
{
  assert(cloudbox_limits.nelem() == 6);
  const Index np = ppath_step.np;
 
  return is_gp_inside_cloudbox(ppath_step.gp_p[np - 1],
                               ppath_step.gp_lat[np - 1],
                               ppath_step.gp_lon[np - 1],
                               cloudbox_limits,
                               include_boundaries);
}
 
void bin_quadweights(Vector& w, const Vector& x, const Index& order) {
  Index nx = x.nelem();
 
  assert(nx > 1);
  assert(is_increasing(x));
 
  if (order == 0) {
    w[0] = min(x[1] - x[0],
               0.5 * (x[1] + x[0]));  // the latter is the half distance
                                      // from x0 to x1 plus the distance
                                      // to 0, ie 0.5(x1-x0)+x0.
    w[nx - 1] = x[nx - 1] - x[nx - 2];
  } else {
    w[0] = 0.5 * (x[1] - x[0]);
    w[nx - 1] = 0.5 * (x[nx - 1] - x[nx - 2]);
  }
  for (Index i = 1; i < nx - 1; i++) {
    w[i] = 0.5 * (x[i + 1] - x[i - 1]);
  }
}
 
 
void chk_scat_species_field(bool& empty_flag,
                            const Tensor3& scat_species_field,
                            const String& fieldname,
                            const Index& dim,
                            const Vector& p_grid,
                            const Vector& lat_grid,
                            const Vector& lon_grid) {
  // check p
  if (scat_species_field.npages() != p_grid.nelem()) {
    ostringstream os;
    os << "The size of *p_grid* (" << p_grid.nelem()
       << ") is unequal the number of pages of *" << fieldname << "* ("
       << scat_species_field.npages() << ").";
    throw runtime_error(os.str());
  }
 
  // check lat
  if (dim >= 2) {
    if (scat_species_field.nrows() != lat_grid.nelem()) {
      ostringstream os;
      os << "The size of *lat_grid* (" << lat_grid.nelem()
         << ") is unequal the number of rows of *" << fieldname << "* ("
         << scat_species_field.nrows() << ").";
      throw runtime_error(os.str());
    }
  }
 
  // check lon
  if (dim == 3) {
    if (scat_species_field.ncols() != lon_grid.nelem()) {
      ostringstream os;
      os << "The size of *lon_grid* (" << lon_grid.nelem()
         << ") is unequal the number of columns of *" << fieldname << "* ("
         << scat_species_field.ncols() << ").";
      throw runtime_error(os.str());
    }
  }
 
  empty_flag = false;
  // set empty_flag to true if a single value of hydromet_field is unequal zero
  for (Index j = 0; j < scat_species_field.npages(); j++) {
    for (Index k = 0; k < scat_species_field.nrows(); k++) {
      for (Index l = 0; l < scat_species_field.ncols(); l++) {
        if (scat_species_field(j, k, l) != 0.0 &&
            !std::isnan(scat_species_field(j, k, l)))
          empty_flag = true;
        //            if ( scat_species_field(j,k,l) != 0.0 ) empty_flag = true;
      }
    }
  }
}
 
 
void find_cloudlimits(Index& lower,
                      Index& upper,
                      const Tensor3& scat_species_field,
                      const Index& atmosphere_dim,
                      const Numeric& cloudbox_margin) {
  if (atmosphere_dim == 1) {
    // scattering species profiles
    ConstVectorView ss_prof = scat_species_field(joker, 0, 0);
 
    Index i = 0;
 
    // find lower cloudbox_limit to surface if margin != -1 (cloudbox not
    // forced to reach down to surface)
    if (cloudbox_margin != -1) {
      // find index of first pressure level where hydromet_field is
      // unequal 0, starting from the surface
      for (i = 0; i < lower; i++) {
        //cout << "for lower limit checking level #" << i << "\n";
 
        // if any of the scat species fields contains a non-zero, non-NaN
        // value at this atm level we found a potential lower limit value
        if (ss_prof[i] != 0.0 && !std::isnan(ss_prof[i])) {
          //cout << "found particles\n";
 
          // check if lower is the lowest index in all selected
          // scattering species fields
          if (lower > i) {
            lower = i;
            //cout << "new lower limit at level #" << lower << "\n";
          }
          break;
        }
      }
    }
 
    // find index of highest pressure level, where scat_species_mass_density_field is
    // unequal 0, starting from top of the atmosphere
    for (Index j = scat_species_field.npages() - 1; j >= max(i, upper); j--) {
      //cout << "for upper limit checking level #" << j << "\n";
 
      // if any of the scat species fields contains a non-zero, non-NaN
      // value at this atm level we found a potential lower limit value
      if (ss_prof[j] != 0.0 && !std::isnan(ss_prof[j])) {
        //cout << "found particles\n";
 
        // check if upper is the highest index in all selected
        // scattering species fields
        if (upper < j) {
          upper = j;
          //cout << "new upper limit at level #" << upper << "\n";
        }
        break;
      }
    }
  }
 
  else {
    ostringstream os;
    os << "Not yet available for 2D and 3D cases.";
    throw runtime_error(os.str());
  }
 
  /*  //NOT WORKING YET
      // Latitude limits
      else if ( atmosphere_dim == 2 )
      {
        MatrixView hydro_lat = hydromet_field ( nhyd, joker, joker, 0 );
 
        for ( i=0; i<hydro_lat.nrows(); i++ )
        {
          for ( j=0; j<hydro_lat.ncols(); j++ )
          {
            if ( hydro_lat[i,j] != 0.0 )
            {
 
              if ( lat1 <= j ) lat1 =j;
              //cloudbox_limits[2] = lat1;
              //break;
            }
 
          }
          if ( lower <= i )    lower = i;
        }
 
        for ( k=hydro_lat.nelem()-1; k>=i; k-- )
        {
          if ( hydro_lat[k] != 0.0 )
          {
            lat2 = k;
            cloudbox_limits[3] = lat2;
            break;
 
          }
 
        }
      }
 
      // Longitude limits
      if ( atmosphere_dim == 3 )
      {
        Tensor3View hydro_lon = hydromet_field ( nhyd, joker, joker, joker );
 
        for ( i=0; i<hydro_lon.nelem(); i++ )
        {
          if ( hydro_lon[i] != 0.0 )
          {
            lon1 = i;
            cloudbox_limits[4] = lon1;
            break;
          }
 
        }
        for ( j=hydro_lon.nelem()-1; j>=i; j-- )
        {
          if ( hydro_lon[j] != 0.0 )
          {
            lon2 = j;
            cloudbox_limits[5] = lon2;
            break;
 
          }
}*/
}
 
void parse_atmcompact_speciestype(  //WS Output:
    String& species_type,
    // WS Input:
    const String& field_name,
    const String& delim) {
  ArrayOfString strarr;
 
  // split field_name string at '-' and write to ArrayOfString
  field_name.split(strarr, delim);
 
  // first entry is species type
  // (i.e. "abs_species" or "scat_species". or "T" or "z", which are ignored.)
  if (strarr.size() > 0 && field_name[0] != '-') {
    species_type = strarr[0];
  } else {
    ostringstream os;
    os << "No information on field species type found in '" << field_name
       << "'\n";
    throw runtime_error(os.str());
  }
}
 
void parse_atmcompact_speciesname(  //WS Output:
    String& species_name,
    // WS Input:
    const String& field_name,
    const String& delim) {
  ArrayOfString strarr;
 
  // split field_name string at '-' and write to ArrayOfString
  field_name.split(strarr, delim);
 
  // second entry is species name
  // (e.g. "H2O, "O3" etc. for abs_species or "IWC", "LWC" etc. for scat_species)
  if (strarr.size() > 1) {
    species_name = strarr[1];
  } else {
    ostringstream os;
    os << "No information on field species name found in '" << field_name
       << "'\n";
    throw runtime_error(os.str());
  }
}
 
void parse_atmcompact_scattype(  //WS Output:
    String& scat_type,
    // WS Input:
    const String& field_name,
    const String& delim) {
  ArrayOfString strarr;
 
  // split field_name string at '-' and write to ArrayOfString
  field_name.split(strarr, delim);
 
  // third entry is type of scat_species field
  // (e.g. "mass_density", "mass_flux", "number_density")
  if (strarr.size() > 2) {
    scat_type = strarr[2];
  } else {
    ostringstream os;
    os << "No information on type of scat_species field found in '"
       << field_name << "'\n";
    throw runtime_error(os.str());
  }
}
 
void parse_partfield_name(  //WS Output:
    String& partfield_name,
    // WS Input:
    const String& part_string,
    const String& delim) {
  ArrayOfString strarr;
 
  // split scat_species string at delim and write to ArrayOfString
  part_string.split(strarr, delim);
 
  //first entry is scattering species field name (e.g. "IWC", "LWC" etc.)
  if (strarr.size() > 0 && part_string[0] != delim[0]) {
    partfield_name = strarr[0];
  } else {
    ostringstream os;
    os << "No information on scattering species field name in '" << part_string
       << "'\n";
    throw runtime_error(os.str());
  }
}