% ARTS_GET_FIELDS   Interpolates a raw atmosphere through ARTS
%
%    The function extracts the atmospheric fields that would be used
%    by ARTS for given settings if Q.USE_RAW_ATMOSPHERE = 1. That is,
%    the field USE_RAW_ATMOSPHERE is locally set to 1 before calling ARTS.
%
%    Needed Qarts fields:
%       GAS_SPECIES
%       ATMOSPHERE_DIM
%       RAW_ATMOSPHERE
%    and
%       P_GRID
%       LAT_GRID
%       LON_GRID
%    if not corresponding optional arguments are used.
%
% FORMAT   [t_field,z_field,vmr_field] = arts_get_atmfields( Q, p, lat, lon )
%        
% OUT   t_field     As the ARTS WSV with same name.
%       z_field     As the ARTS WSV with same name.
%       vmr_field   As the ARTS WSV with same name.
% IN    Q           Qarts structure
% OPT   p           If given replaces Q.P_GRID
%       lat         If given replaces Q.LAT_GRID
%       lon         If given replaces Q.LON_GRID

% 2004-09-11   Created by Patrick Eriksson.


function [t_field,z_field,vmr_field] = arts_get_atmfields(Q,p,lat,lon)

if nargin >= 2
  Q.P_GRID = p;
end
if nargin >= 3
  Q.LAT_GRID = lat;
end
if nargin >= 4
  Q.LON_GRID = lon;
end

Q.USE_RAW_ATMOSPHERE = 1;

tmpfolder   = create_tmpfolder;

parts = {'start','load_atm','save_atm','stop'};
S = qarts2cfile( Q, parts, tmpfolder );
cfile = fullfile( tmpfolder, 'cfile.arts' );
qtool( S, cfile, [] );
arts( cfile );
t_field   = xmlLoad( fullfile( tmpfolder, 't_field.xml') );
z_field   = xmlLoad( fullfile( tmpfolder, 'z_field.xml') );
vmr_field = xmlLoad( fullfile( tmpfolder, 'vmr_field.xml') );

delete_tmpfolder( tmpfolder );