d1r4.txt

VB常用数值算法集2

Private Sub Command1_Click()
    'program D1R4
    'Driver program for routine PENDAG
    N = 7
    Dim A(7), B(7), C(7), D(7), E(7), R(7), U(7), A1(7, 7), X(7)
    '输入已知的方程组的系数矩阵
    For I = 1 To N
        For J = 1 To N
        A1(I, J) = 0
        Next J
    Next I
    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
    '输入已知的方程组的右端向量
    R(1) = 1
    R(2) = 2
    R(3) = 3
    R(4) = 4
    R(5) = 5
    R(6) = 6
    R(7) = 7
    Print
    Print Tab(5); "已知的方程组的右端向量"
    Print Tab(14); Format$(R(1), "#.##")
    Print Tab(14); Format$(R(2), "#.##")
    Print Tab(14); Format$(R(3), "#.##")
    Print Tab(14); Format$(R(4), "#.##")
    Print Tab(14); Format$(R(5), "#.##")
    Print Tab(14); Format$(R(6), "#.##")
    Print Tab(14); Format$(R(7), "#.##")
    For I = 3 To N
        A(I) = A1(I, I - 2)
    Next I
    For I = 2 To N
        B(I) = A1(I, I - 1)
    Next I
    For I = 1 To N - 1
        D(I) = A1(I, I + 1)
    Next I
    For I = 1 To N - 2
        E(I) = A1(I, I + 2)
    Next I
    For I = 1 To N
        C(I) = A1(I, I)
    Next I
    Call PENDAG(A(), B(), C(), D(), E(), R(), U(), N)
    Print
    Print Tab(5); "计算出的方程组的解"
    Print Tab(10); Format$(U(1), "#.####E+00")
    Print Tab(10); Format$(U(2), "#.####E+00")
    Print Tab(10); Format$(U(3), "#.####E+00")
    Print Tab(10); Format$(U(4), "#.####E+00")
    Print Tab(10); Format$(U(5), "#.####E+00")
    Print Tab(10); Format$(U(6), "#.####E+00")
    Print Tab(10); Format$(U(7), "#.####E+00")
    '将计算出的解乘以系数矩阵，以验证计算结果正确
    For L = 1 To N
        X(L) = 0#
        For J = 1 To N
            X(L) = X(L) + A1(L, J) * U(J)
        Next J
    Next L
    Print
    Print Tab(5); "计算出的解乘以系数矩阵的结果"
    Print Tab(14); Format$(X(1), "##.##")
    Print Tab(14); Format$(X(2), "##.##")
    Print Tab(14); Format$(X(3), "##.##")
    Print Tab(14); Format$(X(4), "##.##")
    Print Tab(14); Format$(X(5), "##.##")
    Print Tab(14); Format$(X(6), "##.##")
    Print Tab(14); Format$(X(7), "##.##")
End Sub