function [bonds,components] = rbg2abg(name,rbonds,rstrokes,rcomponents,port_coord,port_name,infofile)

% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %% Version control history
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %% $Id$
% %% $Log$
% %% Revision 1.30  1998/07/02 13:40:50  peterg
% %% Added extra ports names (due to defaults) to relevant lists:
% %% 	port_name
% %% 	port_bond
% %%
% %% Revision 1.29  1998/07/02 13:28:31  peterg
% %% Added defaults in new form BEFORE alias expansion
% %%
% %% Revision 1.28  1998/07/02 12:36:05  peterg
% %% Removed debugging lines
% %%
% %% Revision 1.27  1998/07/02 12:24:02  peterg

  direction = -sign(bond_end-1.5*one);
  signed_bond_list = bond_list.*direction;
  components = add_bond(components,signed_bond_list',i);
  
  # Unalias all the ports on this component - if not a junction
  unlabelled_ports = 0;  
  in_bonds = 0;
  if ((comp_type!="0")&&(comp_type!="1")) # Don't do junctions


    for j=1:n_comp_bonds
      signed_bond = signed_bond_list(j);
      port_name_index = getindex(port_bond,signed_bond);
      port_direction = sign(signed_bond);
      
      if port_name_index==0	# There is no port on this bond - so try
				# to default
	unlabelled_ports++;
	if(unlabelled_ports==1)
	  if port_direction>0
	    in_bonds++;
	    port_name_i = "in";
	  else
	    port_name_i = "out";
	  end;
	elseif (unlabelled_ports==2)
	  if port_direction>0
	    if (++in_bonds>1)
	      mtt_info(["More than one unlabelled in port on component " \
			comp_name " (" comp_type ")"],fnum);
	    else
	      port_name_i = "in";
	    end
	  else
	    port_name_i = "out";
	  end;
	else
	  mtt_info(["More than two unlabelled ports on component " \
		    comp_name " (" comp_type ")"],fnum);
        end
	mtt_info(["Defaulting port name [" port_name_i "]\t on component " \
		  comp_name " (" comp_type ")" ],fnum);
	port_name = [port_name; ["[" port_name_i "]"]];	# add to list
	[port_name_index,junk] = size(port_name); # the corresponding
				# index
	port_bond(port_name_index,:) = signed_bond; # add to port bond
      else  
      	port_name_i = deblank(port_name(port_name_index,:));
	port_name_i = port_name_i(2:length(port_name_i)-1) # strip []
      end;
      
      % Replace by alias -- if any
    	eval( ["alias = ", comp_type, '_alias';]); # Get aliases
    	if is_struct(alias)		# are there any aliases
          if struct_contains(alias,port_name_i) # Is this an alias?
	    eval(["new_port_name_i = alias.",port_name_i]);
	    mtt_info(["Expanding  port name [" port_name_i "]\t on component " \
		      comp_name " (" comp_type ")\t to [" new_port_name_i "]"],fnum);
	    port_name = replace_name(port_name, \
				     ["[",new_port_name_i,"]"], \
				     port_name_index);
	  end
      	end
      end
    end

  end;
% At this point, every port should be labeled (port_name) and \
% associated with a bond (port_bond).
disp("--- Completed portnames and the corresponding bonds ---")
port_name, port_bond



% Deduce causality from the strokes (if any) and create the list of bonds
causality = zeros(n_bonds,2);
if n_strokes>0
  % Find out location of centre and ends of stroke.
  stroke_end_1 = [rstrokes(:,1) rstrokes(:,2)];
  stroke_end_2 = [rstrokes(:,3) rstrokes(:,4)];

  end;
end;

bonds = causality;

% Now expand vector ports
[n_bonds,junk] = size(bonds);
n_ports=length(port_bond);
n_exp_ports=n_ports;
exp_port_name="";
exp_port_bond = [];
%exp_comps = [];
for i=1:n_ports
  port_name_i = port_name(i,:)
  [subport,n_subports] = split_port(port_name_i, ','); % Find the components of the vector port