PROGRAM d10r6(input,output);
(* driver for routine POWELL *)

(*$I MODFILE.PAS *)

CONST
   ndim = 3;
   ftol = 1.0e-6;
TYPE
   RealArrayNP = ARRAY [1..ndim] OF real;
   RealArrayNPbyNP = ARRAY [1..ndim,1..ndim] OF real;
   RealArray3 = RealArrayNP;
VAR
   LinminNcom: integer;
   LinminPcom,LinminXicom: RealArrayNP; 
   fret: real;
   i,iter,j: integer;
   p: RealArrayNP;
   xi: RealArrayNPbyNP;

(*$I BESSJ0.PAS *)

FUNCTION fnc(VAR x: RealArray3): real;
(* Programs using FNC must define the type
TYPE
   RealArray3 = ARRAY [1..3] OF real;
in the main routine. *)
BEGIN
   fnc := 0.5-bessj0(sqr(x[1]-1.0)+sqr(x[2]-2.0)+sqr(x[3]-3.0))
END;

(*$I F1DIM.PAS *)

(*$I MNBRAK.PAS *)

(*$I BRENT.PAS *)

(*$I LINMIN.PAS *)

(*$I POWELL.PAS *)

BEGIN
   xi[1,1] := 1.0; xi[1,2] := 0.0; xi[1,3] := 0.0;
   xi[2,1] := 0.0; xi[2,2] := 1.0; xi[2,3] := 0.0;
   xi[3,1] := 0.0; xi[3,2] := 0.0; xi[3,3] := 1.0;
   p[1] := 1.5; p[2] := 1.5; p[3] := 2.5;
   powell(p,xi,ndim,ftol,iter,fret);
   writeln('Iterations:',iter:3);
   writeln;
   writeln('Minimum found at: ');
   FOR i := 1 TO ndim DO write(p[i]:12:6);
   writeln;
   writeln;
   writeln('Minimum function value =',fret:12:6);
   writeln;
   writeln('True minimum of function is at:');
   writeln(1.0:12:6,2.0:12:6,3.0:12:6)
END.