d8r2.txt

Numeric Programs

implementation
//PROGRAM D8R2
//Driver for routine ZBRAC
uses
  unit2;
  {$R *.DFM}
Function FUN(X:real):real;
begin
    FUN:= BESSJ0(X);
end;

procedure TForm1.Button1Click(Sender: TObject);
const
  s1='%14.6f';  s2='%8.2f';
var
  F:TextFile; SUCCES:boolean;
  I:integer;  X1,X2:real;
begin
  //输出计算结果到文件
  AssignFile(F, 'd:\delphi_shu\p8\d8r2.dat');
  Rewrite(F);
  Writeln(F, '  Bracketing values:      Function values:');
  Writeln(F);
  Writeln(F, '     X1      X2      BESSJ0(X1)    BESSJ0(X2)');
  Writeln(F);
  For I:= 1 To 10 do
  begin
    X1:= I;
    X2:= X1 + 1;
    ZBRAC(X1, X2, SUCCES);
    If SUCCES Then
    Writeln(F, Format(s2,[X1]),Format(s2,[X2]),Format(s1,[BESSJ0(X1)]),
               Format(s1,[BESSJ0(X2)]));
  end;
  CloseFile(F);
  //屏幕显示计算结果
  memo1.Lines.LoadFromFile('d:\delphi_shu\p8\d8r2.dat');
end;