function structure = R_eqn(name,bond_number,bonds,direction,cr,args, ...
structure,eqnfile);
% R_eqn - Equation function for a (multi-port) unicausal R component
%
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %%%%% Model Transformation Tools %%%%%
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% Matlab function R_eqn
% structure = R_eqn(name,bond_number,bonds,direction,cr,args, ...
% structure,eqnfile)
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %% Version control history
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %% $Id$
% %% $Log$
% %% Revision 1.3 1996/09/12 16:40:45 peter
% %% Now does a default (when no constitutive relationship) with a unit
% %% constitutive relationship on each port.
% %%
% %% Revision 1.2 1996/09/12 13:12:04 peter
% %% Removed an fprintf that was a mistake.
% %%
% %% Revision 1.1 1996/09/12 11:00:56 peter
% %% Initial revision
% %%
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Copyright (c) P.J. Gawthrop, 1996.
if nargin<8
eqnfile = 'stdout';
end;
% Find the number of ports
[ports,junk] = size(bonds);
for outport = 1:ports
outcause = -bonds(outport,1);
outnumber = bond_number(outport);
if length(cr)>0
incause = bonds(:,1);
inport = 1:ports;
inbond = bond_number;
else % default if no cr: unit cr on each port
incause = bonds(outport,1);
inport = outport;
inbond = outnumber;
end;
eqn = equation(name,cr,args,outnumber,outcause,outport, ...
inbond,incause,inport);
fprintf(eqnfile, '%s',eqn);
end;