d2r1.txt

用于开发税务票据管理的软件

implementation
//PROGRAM D2R1
//Driver for routine POLINT
uses
  unit2;
  {$R *.DFM}
procedure TForm1.Button1Click(Sender: TObject);
var
  XA,YA:array[0..10] of real;
  X,Y,FF,DY:real;
  F:TextFile;  I,NFUNC:Integer;
const
  N=9; PI=3.1415926; s1='%12.6f'; s2='0.0000E+00';
begin
  //输出计算结果到文件
  AssignFile(F, 'd:\delphi_shu\p2\d2r1.dat');
  Rewrite(F);
  Writeln(F, 'Generation of interpolation tables');
  Writeln(F,'... sin(x)    0<x<PI');
  Writeln(F,'... exp(x)     0<x<1');
  Writeln(F,'How many entries go in these tables?(Note: N<10)');
  Writeln(F,N);
  For NFUNC:=1 To 2 do
  begin
      If NFUNC = 1 Then
      begin
          Writeln(F,'sine function from 0 to PI');
          For I:=1 To N do
          begin
              XA[I]:=I * PI / N;
              YA[I]:=Sin(XA[I]);
          end;
      end
      else
      begin
          Writeln(F,'exponential function from 0 to 1');
          For I:=1 To N do
          begin
              XA[I]:=I / N;
              YA[I]:=Exp(XA[I]);
          end;
      end;
      Writeln(F,'       x           f(x)    interpolated   error');
      For I:=1 To 10 do
      begin
          If NFUNC = 1 Then
          begin
              X:=(-0.05 + I / 10) * PI;
              FF:=Sin(X);
          end
          else
          begin
              X:=(-0.05 + I / 10);
              FF:=Exp(X);
          end;
          POLINT(XA, YA, N, X, Y, DY);
          Writeln(F,Format(s1,[X]),Format(s1,[FF]),Format(s1,[Y]),
                   '    ',FormatFloat(s2,DY));
      end;
  end;
  CloseFile(F);
  //屏幕显示计算结果
  memo1.ScrollBars:=ssVertical;
  memo1.Lines.LoadFromFile('d:\delphi_shu\p2\d2r1.dat');
end;