function [] = latex_labels(varargin)
%function [] = latex_labels(fig_no, fig_width, file_name,
%      font_size, val1, str1, val2, str2, ... )
%
% This function uses a slightly edited version of fragmaster.pl
% (www.tat.physik.uni-tuebingen.de/~vogel/fragmaster/main.html)
% to give latex labels to matlab text.
%
% VARIABLES
%  fig_no: Figure Handle (e.g. figure(1)), default is active figure.
%  fig_width: Width of figure in inches
%  file_name: name of desired file without extension
%  font_size: font size (in points) for labels
%  val/str pairs (described below): text in matlab and latex
%       replacement
%  
% VAL/STR pairs
%  these are the pairs that are changed by the script
%  for example, the pair 'x', '$x$' will replace the matlab "x"
%  with the latex $x$. (NOTE: The matlab value cannot contain any
%  spaces and must be the complete string, i.e. the method will not
%  replace subsets of a string.)
%
% The function runs, Perl, LaTeX and dvips. 
% It requires its sister file, latex_labels.perl, and the
% LaTeX style file, psfrag.sty. It is set up by default to also 
% include amsmath.sty. Packages can be added or removed 
% near the end of the file. (If you don't have psfrag.sty or
% amsmath.sty, you will need to acquire them.)
%
% NOTES
%  - Some fields need editing (see top of matlab file)
%  - Written for implimentation on a UNIX/Linux system,
%      and will likely need tweaking for Windows
%
% EXAMPLE:
%
%   x = [-5:5];
%   y = x.^2;
%   plot(x,y);
%   xlabel('x');
%   ylabel('y');
%   set(gca,'fontname','times');
%   latex_labels([], 6, 'yequalxsqrd', 12, 'x', '$x$', ...
%	       'y', '$y=x^2$');
% 

%                              RSM||13Mar07
%                              ramzi@dal.ca

% FIELDS THAT MAY NEED EDITING
perl_path = ['~/matlab/']; % path to latex_labels.perl



if(length(varargin) < 6 | ...
   length(varargin)/2 ~= round(length(varargin)/2))
  error(['Incorrect number of inputs for latex_labels.m']);
end


if(~isempty(varargin{1}))
  figure(fig_no);
end
if(~isnumeric(varargin{2}))
  error(['figure width must be a number in latex_labels.m']);
else
  fig_width = varargin{2};
end
if(~isstr(varargin{3}))
  error(['file name must be a string in latex_labels.m']);
else
  file_name = varargin{3};
end

if(~isnumeric(varargin{4}))
  error(['font size must be a number in latex_labels.m']);
else
  font_size = varargin{4};
end

% make "control file"
fid = fopen([file_name,'_fm'],'w');
str = ['% Just an ordinary comment\n', ...
       '%\n', ...
       '% A special comment:\n', ...
       '% fmopt:width=', num2str(fig_width), 'in\n', ...
       '% \n', ...
       '% Another special comment:\n', ...
       '% head:\n', ...
       '% \usepackage{amsmath}\n', ...
       '% end head\n', ...
       '\n', ...
       '% psfrag commands:\n'];

frags = [];
m = 4;
while(m < length(varargin))
  frags = [frags, ...
	   '\psfrag{', varargin{m+1}, '}{', varargin{m+2} ,'}\n'];
  m = m + 2;
end
       
fprintf(fid, '%s', str);
fprintf(fid, '%s', frags);

fclose(fid);

eval(['print -depsc2 ', file_name ,'_fm.eps']);
eval(['!perl -pi -e ''s/\\n/\n/g'' ', file_name ,'_fm']);
eval(['!perl ', perl_path, 'latex_labels.perl ', ...
      file_name, '_fm ', num2str(font_size)]);

eval(['!rm ', file_name, '_fm ', file_name ,'_fm.eps']);