PROGRAM d9r11(input,output);
(* driver for routine ZROOTS *)
CONST
   m=4;
   twomp2=10;   (* twomp2=(2*m+2) *)
TYPE
   glcarray = ARRAY [1..twomp2] OF real;
   gl2array = ARRAY [1..2] OF real;
VAR
   i : integer;
   polish : boolean;
   a,roots : glcarray;

(*$I MODFILE.PAS *)
(*$I LAGUER.PAS *)

(*$I ZROOTS.PAS *)

BEGIN
   a[1] := 0.0; a[2] := 2.0;
   a[3] := 0.0; a[4] := 0.0;
   a[5] := -1.0; a[6] := -2.0;
   a[7] := 0.0; a[8] := 0.0;
   a[9] := 1.0; a[10] := 0.0;
   writeln('Roots of the polynomial x^4-(1+2i)*x^2+2i');
   polish := false;
   zroots(a,m,roots,polish);
   writeln;
   writeln('Unpolished roots:');
   writeln('root #':14,'real':13,'imag.':13);
   FOR i := 1 to m DO BEGIN
      writeln(i:11,' ':5,roots[2*i-1]:12:6,roots[2*i]:12:6)
   END;
   writeln;
   writeln('Corrupted roots:');
   FOR i := 1 to m DO BEGIN
      roots[2*i-1] := roots[2*i-1]*(1+0.01*i);
      roots[2*i] := roots[2*i]*(1+0.01*i)
   END;
   writeln('root #':14,'real':13,'imag.':13);
   FOR i := 1 to m DO BEGIN
      writeln(i:11,' ':5,roots[2*i-1]:12:6,roots[2*i]:12:6)
   END;
   polish := true;
   zroots(a,m,roots,polish);
   writeln;
   writeln('Polished roots:');
   writeln('root #':14,'real':13,'imag.':13);
   FOR i := 1 to m DO BEGIN
      writeln(i:11,' ':5,roots[2*i-1]:12:6,roots[2*i]:12:6)
   END
END.