(* Algorithmus 7.1 *)
FUNCTION trapez(a,b,eps:real):real;
VAR h,s,ta,tn : real; j,zh : integer;
    (* GLOBALE Funktion f : real *)
BEGIN
   h:=b-a; s:=(f(a)+f(b))/2;
   tn:= h*s; zh:=1;
   REPEAT
     ta:=tn; zh:=2*zh; h:=h/2;
     j:=1;
     REPEAT
       s:=s+f(a+j*h); j:=j+2
     UNTIL j>zh;
     tn := h*s;
     writeln(tf,zh:8,tn:25);
   UNTIL abs(ta-tn)<=eps*abs(tn);
   trapez := tn;
END;