function updateTsgStruct(hMainFig)
%
% This function is called after reading data and update tsg structure
% with common values
%
% Input
% -----
% hMainFig ............ Handel to the main user interface
%
% $Id$

% Get the data from the application GUI
% -------------------------------------
tsg = getappdata( hMainFig, 'tsg_data');

nPARA = 2;
PARA  = ['SSPS'; 'SSJT'];

% get min and max values for position and set to globals attributes
% -----------------------------------------------------------------
tsg.SOUTH_LATX = min(tsg.LATX);
tsg.NORTH_LATX = max(tsg.LATX);
tsg.WEST_LONX  = min(tsg.LONX);
tsg.EAST_LONX  = max(tsg.LONX);

% get date start and end value and set to globals attributes
% -----------------------------------------------------------------
date           = datestr(min(tsg.DAYD),30);
tsg.DATE_START = [date(1:8) date(10:15)];
date           = datestr(max(tsg.DAYD),30);
tsg.DATE_END   = [date(1:8) date(10:15)];

% Compute ship velocity from positions if sog not available
% ---------------------------------------------------------
if isempty(tsg.SPDC)
  range    = m_lldist(tsg.LONX,tsg.LATX);
  ind      = size(tsg.DAYD);
  tsg.SPDC = zeros(size(ind));
  
  for i=1:length(tsg.DAYD)-1
    tsg.SPDC(i) = range(i) / ((tsg.DAYD(i+1)-tsg.DAYD(i)) * 24 * 1.854);
  end
  tsg.SPDC = [tsg.SPDC';0];
end

% Varaibles must exists
% ---------------------
for i = 1: nPARA

  para1 =  PARA(i,:);
  if isempty( tsg.(para1) )
    msgbox(['You must initialise the tsg.' PARA(i,:) ' variable'],...
      'function ''updateTsgStruct''', ....
      'warn', 'modal');
  end
end

% Empty variables filled with NaN
% -------------------------------
names = fieldnames( tsg );
for i = 1: length(names)
  para = char( names(i) );
  if ~isstruct( tsg.(para) ) && ~isempty( tsg.(para) )
    A = tsg.(para);
    ind = find( isnan( A ) == 0 );
    if isempty( ind )
      tsg.(para) = [];
    end
  end
end

% Initialise  'variables_LINCOEF'
% -------------------------------
if isempty(tsg.SSJT_LINCOEF)
  tsg.SSJT_LINCOEF(1) = 1;
  tsg.SSJT_LINCOEF(2) = 0;
end
if isempty(tsg.CNDC_LINCOEF)
  tsg.CNDC_LINCOEF(1) = 1;
  tsg.CNDC_LINCOEF(2) = 0;
end
if isempty(tsg.SSTP_LINCOEF)
  tsg.SSTP_LINCOEF(1) = 1;
  tsg.SSTP_LINCOEF(2) = 0;
end

% Save tsg structure 
% ------------------
setappdata( hMainFig, 'tsg_data', tsg);