PROGRAM d6r28(input,output);
(* driver for routine EL2 *)

(*$I MODFILE.PAS *)

TYPE
   RealArray55 = ARRAY [1..55] OF real;
VAR
   TrapzdIt: integer;
   Ran3Inext,Ran3Inextp: integer;
   Ran3Ma: RealArray55;
   FuncA,FuncB,FuncAkc: real;
   ago,astop,s,x: real;
   i,idum: integer;

FUNCTION func(phi: real): real;
(* Programs using routine FUNC must declare the variables
VAR
   FuncAkc,FuncA,FuncB: real;
in the main routine, and must assign their values. *)
VAR
   tn,tsq: real;
BEGIN
   tn := sin(phi)/cos(phi);
   tsq := tn*tn;
   func := (FuncA+FuncB*tsq)/sqrt((1.0+tsq)*(1.0+FuncAkc*FuncAkc*tsq))
END;

(*$I RAN3.PAS *)

(*$I TRAPZD.PAS *)

(*$I QSIMP.PAS *)

(*$I EL2.PAS *)

BEGIN
   writeln('general elliptic integral of second kind');
   writeln('x':7,'kc':10,'a':10,'b':10,'el2':11,'integral':12);
   idum := -55;
   ago := 0.0;
   FOR i := 1 TO 20 DO BEGIN
      FuncAkc := 5.0*ran3(idum);
      FuncA := 10.0*ran3(idum);
      FuncB := 10.0*ran3(idum);
      x := 10.0*ran3(idum);
      astop := arctan(x);
      qsimp(ago,astop,s);
      writeln(x:10:6,FuncAkc:10:6,FuncA:10:6,FuncB:10:6,
         el2(x,FuncAkc,FuncA,FuncB):10:6,s:10:6)
   END
END.