%------------------------------------------------------------------------
% NAME:     qpi_Kx
%
%           Inline function to include calculation of the Kx matrix in
%           the control file.
%
% FORMAT:   qpi_Kx( Q, fid )
%
% OUT:      -
% IN:       Q     Setting structure
%           fid   File identifier for the control file being created.
%------------------------------------------------------------------------

% HISTORY: 2001.03.28  Created by Patrick Eriksson


function qpi_Kx( Q, fid )


%=== Determine the length of x ================================================
%
nx = 0;
ni = 0;

%= Species
%
nspecies = sstring_length( Q.RETRIEVAL_TAGS );
%
for i = 1:nspecies
  name    = sstring_get_i( Q.SPECIES_KGRIDS, i );
  grid    = read_datafile( [ Q.RETRIEVDEF_DIR, '/', name ], 'VECTOR');
  nx      = nx + length(grid);
  ni      = ni + 1;
end


%= Temperature
%
if Q.TEMPERATURE_DO == 3
  name    = Q.TEMPERATURE_KGRID;
  grid    = read_datafile( [ Q.RETRIEVDEF_DIR, '/', name ], 'VECTOR');
  nx      = nx + length(grid);
  ni      = ni + 1;
end


%= Pointing
%
if Q.POINTING_DO == 3
  nx = nx + 1;
  ni = ni + 1;
end


%= Continuum absorption
%
if Q.CONTABS_DO == 3
  name    = Q.CONTABS_KGRID;
  grid    = read_datafile( [ Q.RETRIEVDEF_DIR, '/', name ], 'VECTOR');
  nx      = nx + length(grid)*(Q.CONTABS_ORDER+1);
  ni      = ni + Q.CONTABS_ORDER + 1;
end




%=== Write to cfile ===========================================================

%= Allocate memory for Kx
%
fprintf(fid, 'kxAllocate( y ){\n   ni = %d\n   nx = %d\n}\n', ni, nx ); 


%= Calculate the abs. LOS WFs
fprintf(fid, 'absloswfsCalc{\n}\n');


%= Species
for i = 1:nspecies
  name = [ Q.RETRIEVDEF_DIR, '/', sstring_get_i( Q.SPECIES_KGRIDS, i ) ];
  fprintf(fid, 'VectorReadAscii( k_grid ) {\n  "%s"\n}\n', name );
  name = sstring_get_i( Q.RETRIEVAL_TAGS, i );
  fprintf(fid, 'kSpeciesSingle{\n   tg   = "%s"\n   unit  = "frac"\n}\n', ...
                                                                         name);
  fprintf(fid, 'kxPutInK{\n}\n');
end


%= Temperature
if Q.TEMPERATURE_DO == 3
  name = [ Q.RETRIEVDEF_DIR, '/', Q.TEMPERATURE_KGRID ];
  fprintf(fid, 'VectorReadAscii( k_grid ) {\n  "%s"\n}\n', name );
  fprintf(fid, 'kTemp{\n   hse  = %d\n   fast = 1\n}\n', Q.HSE_RETRIEVAL_ON);
  fprintf(fid, 'kxPutInK{\n}\n');
end


%= Pointing
%
if Q.POINTING_DO == 3
  fprintf(fid, 'kPointingOffSet{\n   delta = %.2e\n}\n',Q.POINTING_DELTA);
  fprintf(fid, 'kxPutInK{\n}\n');
end


%= Continuum absorption in primary band 
%
if Q.CONTABS_DO == 3
  if isempty( Q.CONTABS_LIMITS )
    f_mono = read_datafile( [ Q.CALCGRIDS_DIR, '/', Q.F_MONO ], 'VECTOR');
    lims = [f_mono(1), last(f_mono) ];
  else
    lims = Q.CONTABS_LIMITS;
  end
  name    = [ Q.RETRIEVDEF_DIR, '/', Q.CONTABS_KGRID ];
  fprintf(fid, 'VectorReadAscii( k_grid ) {\n  "%s"\n}\n', name );
  fprintf(fid, 'kContAbs{\n');
  fprintf(fid, '   order  = %d\n', Q.CONTABS_ORDER );
  fprintf(fid, '   f_low  = %.6e\n', lims(1) );
  fprintf(fid, '   f_high = %.6e\n}\n', lims(2) );
  fprintf(fid, 'kxPutInK{\n}\n');
end


%= Convert to RJ temperatures if emission observations
%
if Q.EMISSION_ON
  fprintf(fid, 'MatrixTRJ( kx, kx ) { \n}\n');
end


%= Save kx and additional variables
%
fprintf(fid, 'MatrixWriteBinary( kx ) { \n""\n}\n');  
fprintf(fid, 'ArrayOfIndexWriteBinary( kx_lengths ){ \n""\n}\n');  
fprintf(fid, 'MatrixWriteBinary( kx_aux ){ \n""\n}\n');  
fprintf(fid, 'ArrayOfStringWriteBinary( kx_names ){ \n""\n}\n');