/* Maxima-compatibility definitions */

/* RISC Institute, Linz, Austria    */
/* by Fabrizio Caruso               */


zb_op(expr) := 
  if atom(expr) then
     expr
  else 
     part(expr,0);


zb_operatorp(expr,operator) :=
    if zb_op(expr)=operator then
       true
    else
       false;






