ADDED   mttroot/mtt/lib/comp/simple/juneqn.m
Index: mttroot/mtt/lib/comp/simple/juneqn.m
==================================================================
--- /dev/null
+++ mttroot/mtt/lib/comp/simple/juneqn.m
@@ -0,0 +1,36 @@
+function juneqn(bond_number,bonds,direction,cr,args,jun,eqnfile)
+
+% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% %% Version control history
+% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+% %% $Id$
+% %% $Log$
+% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+
+% Equations for  both  effort and flow on  either zero or one junctions
+
+if nargin<7
+  eqnfile = 'stdout';
+end;
+
+
+
+% Same causality as junction
+column =  (3-jun)/2; 
+[causing_bond,n,other_bonds,m] = getindex(bonds(:,column),jun);
+for i=other_bonds'
+  oneeqn(bond_number(i), jun, bond_number(causing_bond), jun, '', '',eqnfile);
+end;
+
+
+% Opposite causality to junction
+column =  (3+jun)/2;
+[caused_bond,n,other_bonds,m] = getindex(bonds(:,column),jun);
+fprintf(eqnfile, '%s\t:= \n',  varname(bond_number(caused_bond),-jun));
+for i=other_bonds'
+  term_sign = -direction(caused_bond,column)*direction(i,column);
+  fprintf(eqnfile, '\t\t%s %s\n', sign2name(term_sign), ...
+      varname(bond_number(i),-jun));
+end;
+fprintf(eqnfile, ';\n');