d5r2.txt

Numeric Programs

implementation
//PROGRAM D5R2
//Driver for routine DDPOLY
uses
  unit2;
  {$R *.DFM}
procedure TForm1.Button1Click(Sender: TObject);
var
  F:TextFile;   I,J:Integer;
  X,AAA:real;
  A:array[0..5] of string; C,PD:array[0..6] of real;
  D:matrx2;
const
  s1='%14.6f';
  NC = 6; NCM1 = 5; NP = 20;
begin
  Setlength(D,6,21);
  A[1]:='polynomial:';    A[2]:='first deriv:';
  A[3]:='second deriv:';  A[4]:='third deriv:';
  A[5]:='fourth deriv:';
  C[1]:=-1;         C[2]:=5;
  C[3]:=-10;        C[4]:=10;
  C[5]:=-5;         C[6]:=1;
  For I:=1 To NP do
  begin
      X:=0.1 * I;
      DDPOLY(C, NC, X, PD, NC - 1);
      For J:=1 To NC - 1 do
          D[J, I]:=PD[J];
  end;
  //输出计算结果到文件
  AssignFile(F, 'd:\delphi_shu\p5\d5r2.dat');
  Rewrite(F);
  For I:=1 To NC - 1 do
  begin
      Writeln(F,A[I]);
      Writeln(F, '          X          DDPOLY        ACTUAL');
      For J:=1 To NP do
      begin
        X:=0.1 * J;
        if X-1 > 0 THEN
          AAA:=FACTRL(NC - 1) / FACTRL(NC - I) * Exp((NC - I)*Ln(X - 1))
        else if X-1 = 0 then
          AAA:=0
        else if Odd(NC -I) = True then
          AAA:=FACTRL(NC - 1) / FACTRL(NC - I) *(-Exp((NC - I)*Ln(1 - X)))
        else if Odd(NC -I) = False then
          AAA:=FACTRL(NC - 1) / FACTRL(NC - I) *(Exp((NC - I)*Ln(1 - X)));
        Writeln(F,Format(s1,[x]),Format(s1,[D[I, J]]),Format(s1,[AAA]));
      end;
  end;
  CloseFile(F);
  //屏幕显示计算结果
  memo1.Lines.LoadFromFile('d:\delphi_shu\p5\d5r2.dat');
end;