// equi.cmd -- to color edges subject to equiangulation

showequi := { ecount := 0; 
	      foreach edge ee do 
		{ al := ee.length; 
		  nn := 1; 
		  foreach ee.facet ff do 
		    { foreach ff.edge fe do 
			{ if ( fe.id != ee.id ) then 
			   { if ( nn == 1 ) then bl := fe.length 
			     else if ( nn == 2 ) then  cl := fe.length 
			     else if ( nn == 3 ) then  dl := fe.length 
			     else if ( nn == 4 ) then  el := fe.length; 
			     nn := nn + 1; 
                           } 
                        }
		    }; 
                  if ( nn == 5 ) then 
                  if (bl^2+cl^2-al^2)/bl/cl + (dl^2+el^2-al^2)/dl/el < -1e-5 then
		    { set ee color green;  
		      ecount := 1 + ecount 
		      } 
                 }; 
                printf "Found %g edges.\n",ecount;
		show_expr edges where 1 
              }
