implementation
//PROGRAM D1R4
//Driver for routine PENDAG
uses
  unit2;
  {$R *.DFM}
procedure TForm1.Button1Click(Sender: TObject);
var
    A1:matrx2;
    A,B,C,D,E,R,U,X:Array[0..7] of real;
    I,J:Integer;
    F:TextFile;
const
    s1='%10.1f'; s2='0.####0e+0';  N = 7;
begin
  setlength(A1,8,8);
  //輸入已知的方程組的系數矩陣
  A1[1, 1]:=4;A1[1, 2]:=1;A1[1, 3]:=1;
  A1[2, 1]:=1;A1[2, 2]:=5;A1[2, 3]:=2;A1[2, 4]:=2;
  A1[3, 1]:=1;A1[3, 2]:=2;A1[3, 3]:=6;A1[3, 4]:=3;A1[3, 5]:=3;
  A1[4, 2]:=2;A1[4, 3]:=3;A1[4, 4]:=7;A1[4, 5]:=4;A1[4, 6]:=4;
  A1[5, 3]:=3;A1[5, 4]:=4;A1[5, 5]:=8;A1[5, 6]:=5;A1[5, 7]:=5;
  A1[6, 4]:=4;A1[6, 5]:=5;A1[6, 6]:=9;A1[6, 7]:=6;
  A1[7, 5]:=5;A1[7, 6]:=6;A1[7, 7]:=10;
  //輸入已知的方程組的右端向量B
  R[1]:=1;         R[2]:=2;
  R[3]:=3;         R[4]:=4;
  R[5]:=5;         R[6]:=6;
  R[7]:=7;
  //輸出計算結果到文件
  AssignFile(F, 'd:\delphi_shu\p1\d1r4.dat');
  Rewrite(F);
  Writeln(F, '已知的方程組的右端向量');
  For I:= 1 To N do
    Writeln(F,Format(s1,[R[I]]));
  For I:=3 To N do
    A[I]:=A1[I, I-2];
  For I:=2 To N do
    B[I]:=A1[I, I-1];
  For I:=1 To N-1 do
    D[I]:=A1[I, I+1];
  For I:=1 To N-2 do
    E[I]:=A1[I, I+2];
  For I:=1 To N do
    C[I]:=A1[I, I];
  PENDAG(A, B, C, D, E, R, U, N);
  Writeln(F, '計算出的方程組的解');
  For I:= 1 To N do
    Writeln(F,'      ',FormatFloat(s2,U[I]));
  Writeln(F, '將計算出的解B乘以系數矩陣，以驗證計算結果正確');
  For I:=1 To N do
    begin
      X[I]:=0;
      For J:=1 To N do
        X[I]:=X[I] + A1[I, J] * U[J];
    end;
  For I:= 1 To N do
    Writeln(F,Format(s1,[X[I]]));
  CloseFile(F);
  //屏幕顯示計算結果
  memo1.Lines.LoadFromFile('d:\delphi_shu\p1\d1r4.dat');
end;