function structure = cbg2ese(system_name,bonds,eqnfile,infofile)
% cbg2ese(system_name,bonds,infofile)
%
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %%%%% Model Transformation Tools %%%%%
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% Matlab function cbg2ese.m
% Acausal bond graph to causal bond graph: mfile format
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %% Version control history
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %% $Id$
% %% $Log$
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
pc = '%';
if nargin<3
eqnfile = 'stdout';
end;
if nargin<4
infofile = 'stdout';
end;
% Evaluate the system function to get the bonds
fun_name = [system_name, '_cbg']
if exist(fun_name)~=2
mtt_info(['m-file ', fun_name, ' does not exist'], infofile);
else
eval(['bonds=', fun_name, ';']);
fun_name = [system_name, '_abg'];
eval(['[junk,components]=', fun_name, ';']);
% Find number of bonds
[n_bonds,columns] = size(bonds);
if (columns ~= 2)&(n_bonds>0)
error('Incorrect bonds matrix: must have 2 columns');
end;
% Find number of components
[n_components,columns] = size(components);
%Structure matrix [states,nonstates,inputs,outputs]
structure = zeros(1,4);
for i = 1:n_components
comp = nozeros(components(i,:));
bond_list = abs(comp);
direction = sign(comp)'*[1 1];
% Convert from arrow orientated to component orientated causality
comp_bonds = bonds(bond_list,:).*direction;
eval([ '[comp_type,name,cr,args] = ', system_name, '_cmp(i);' ]);
% change name of 0 and 1 components -- matlab doesn't like numbers here
if strcmp(comp_type,'0')
comp_type = 'zero';
end;
if strcmp(comp_type,'1')
comp_type = 'one';
end;
% Invoke the appropriate equation-generating procedure
eqn_name = [comp_type, '_eqn']
if exist(eqn_name)~=2 % Try a compound component
cbg2ese(comp_type,comp_bonds,eqnfile);
else % its a simple component
eval(['structure = ', ...
eqn_name, '(bond_list,comp_bonds,direction,cr,args,structure,eqnfile);' ]);
end;
end;
end;