d12r7.txt

《Delphi常用数值算法集》的配书源码

implementation
//PROGRAM D12R7
//Driver for routine RZEXTR
uses
  unit2;
  {$R *.DFM}
procedure TForm1.Button1Click(Sender: TObject);
const
  s1='%13.6f';  s2 = '%7.4f';  NV = 4;  NUSE = 5;
var
  F:TextFile;   YEST,YZ,DY:array[0..NV] of real;
  I,J,IEST:integer;    DUM,XEST:real;
begin
  //Feed values from a rational function
  //Fn(x)=(1-x+x^3)/(x+1)^n
  //输出计算结果到文件
  AssignFile(F, 'd:\delphi_shu\p12\d12r7.dat');
  Rewrite(F);
  For I:= 1 To 10 do
  begin
    IEST:= I;
    XEST:= 1 / I;
    DUM:= 1 - XEST + Exp(3*Ln(XEST));
    For J:= 1 To NV do
    begin
      DUM:= DUM / (XEST + 1);
      YEST[J]:= DUM;
    end;
    RZEXTR(IEST, XEST, YEST, YZ, DY, NV, NUSE);
    Writeln(F);
    Writeln(F,'IEST= ',FormatFloat('##', I),' XEST= ',Format(s2,[XEST]));
    Writeln(F,'Extrap. Function: ',Format(s1,[YZ[1]]),Format(s1,[YZ[2]]),
                                  Format(s1,[YZ[3]]),Format(s1,[YZ[4]]));
    Writeln(F,'Estimated Error:  ',Format(s1,[DY[1]]),Format(s1,[DY[2]]),
                                  Format(s1,[DY[3]]),Format(s1,[DY[4]]));
  end;
  Writeln(F);
  Writeln(F,'Actual Values:      ','1.0       1.0      1.0      1.0');
  CloseFile(F);
  //屏幕显示计算结果
  memo1.Lines.LoadFromFile('d:\delphi_shu\p12\d12r7.dat');
end;