l_compare.m

function l_compare(varargin)
% Function plots curves from one or more logs onto one plot. If depth units or curve units differ
% they are automatically converted to those of the first curve (if a conversion is known; see
% function "l_unit_conversion")
% Written by: E. R.: September 1, 2000
% Last updated: November 23, 2005: Add cursor tracking and figure export button
%
%            l_compare(varargin)
% INPUT
% varargin   one or more cell arrays; the first element of each cell array is either a log structure,
%            or the keyword 'parameters'. 
%            In the first case the following arguments contain a curve mnemonic, possibly followed by
%            one or more cell arrays with parameters. Each cell array starts with a keyword. The
%            following keywords are allowed:
%            'color'   Color of the curve.
%                      Default: {'color','r'} for the first curve,
%                               {'color','b'} for the second curve, ...
%            'linewidth' Linewidth of the curve
%                      Default{'linewidth',1}
%            'legend'  Legend (annotation) of curve. Default: curve mnemonic       
%
%            If the first element is the keyword 'parameters' the following arguments are cell arrays; 
%            the first element of each cell array is a keyword, the other elements are parameters. 
%            Presently, keywords are:
%            'lloc'   numeric parameter specifying the location of the legend;
%                     Default: {'legend',4}
%            'depths' first and last depth to plot (two comma-separated numbers or a two-element
%                     vector)
%                     Default: {'depths',d_min,d_max}     where "d_min" = min(log.first) and
%                              "d_max" is max(log.last) for all logs used
% EXAMPLES
%            l_compare({log1,'DT',{'color','r'},{'linewidth',2},{'legend','Sonic log'}})
%            l_compare({log1,'DT',{'color','r'}},{log2,'DT',{'color','g--'}},{'parameters',{'lloc',2}})
%            l_compare({log1,'DT'},{log1,'DTCO'})            plots two different curves from the same log

global S4M

if ~iscell(varargin{1})
   varargin={varargin};
end
nargs=length(varargin);

color={'r','b','g','k','c','m','y','r--','b--','g--','k--','c--','m--','y--'};

parameters.lloc=4;
parameters.depths=[];

pfigure
set(gcf,'DoubleBuffer','on')

for ii=nargs:-1:1
   argument=varargin{ii};
   login=argument{1};
   if ~isstruct(login)
      if strcmpi(login,'parameters')
         parameters=assign_input(parameters,argument(2:end));
         break
      else
         error(' First element of input cell array is neither a log nor the keyword "parameters"')
      end
   end
end  

icurve=1;
for ii=1:nargs
  argument=varargin{ii};
  login=argument{1};

            if isstruct(login)

  mnemonic=argument{2};

%       Default settings
  compare.linewidth=2;
  compare.color=color{icurve};
  compare.legend=strrep(mnemonic,'_','\_');

%       Decode and assign input arguments
  if length(argument) > 2
     compare=assign_input(compare,argument(3:end));
  end
  
%       Find requested curve
  idx=curve_index1(login,mnemonic);
  curve_units=login.curve_info{idx,2};
  depth_units=login.curve_info{1,2};

  if icurve == 1
     set(gca,'YDir','reverse','XAxisLocation','top');
     hold on
     old_curve_units=curve_units;
     old_depth_units=depth_units;
     ltext=compare.legend;
     xlabel(units2tex(curve_units),'FontSize',13,'FontWeight','bold','Fontname',S4M.font_name);
     ylabel(info2label(login.curve_info(1,:)), ...
          'FontSize',13,'FontWeight','bold','Fontname',S4M.font_name)
  else
     login=l_unit_conversion(login,{depth_units,old_depth_units},{curve_units,old_curve_units,mnemonic});
     ltext=char(ltext,compare.legend);
  end
 

  curve=login.curves(:,idx);
  depth=login.curves(:,1);
  if ~isempty(parameters.depths)
     if iscell(parameters.depths)
        parameters.depths=cat(2,parameters.depths{:});
     end
     idx=find(depth >= parameters.depths(1) & depth <= parameters.depths(2));
     depth=depth(idx);
     curve=curve(idx);
  end
  plot(curve,depth,compare.color,'LineWidth',compare.linewidth)

  icurve=icurve+1;

            end
end  

timeStamp

legend(ltext,parameters.lloc)
grid, zoom on

%       Add button for cursor tracking and for figure export   
figure_export_menu
initiate_2d_tracking(login.curve_info(idx,:),login.curve_info(1,:))