d1r1.txt

VB常用数值算法集 内含有解线性代数方程组

Private Sub Command1_Click()
    'program D1R1
    'Driver program for routine GAUSSJ
    N = 3
    Dim A(3, 3), B(3), A1(3, 3), B1(3)
    '输入已知的方程组的系数矩阵
    A(1, 1) = 2: A(1, 2) = 1: A(1, 3) = 2
    A(2, 1) = 5: A(2, 2) = -1: A(2, 3) = 1
    A(3, 1) = 1: A(3, 2) = -3: A(3, 3) = -4
    '输入已知的方程组的右端向量B
    B(1) = 5
    B(2) = 8
    B(3) = -4
    Print
    Print Tab(5); "已知的方程组的右端向量"
    Print Tab(14); Format$(B(1), "##.##")
    Print Tab(14); Format$(B(2), "##.##")
    Print Tab(14); Format$(B(3), "##.##")
    For I = 1 To N
        For J = 1 To 3
        A1(I, J) = A(I, J)
        Next J
    Next I
    Call GAUSSJ(A(), N, B())
    Print
    Print Tab(5); "计算出的方程组的解"
    Print Tab(14); Format$(B(1), "##.##")
    Print Tab(14); Format$(B(2), "##.##")
    Print Tab(14); Format$(B(3), "##.##")
    '将计算出的解B乘以系数矩阵，以验证计算结果正确
    For L = 1 To N
        B1(L) = 0#
        For J = 1 To N
            B1(L) = B1(L) + A1(L, J) * B(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$(B1(1), "##.##")
    Print Tab(14); Format$(B1(2), "##.##")
    Print Tab(14); Format$(B1(3), "##.##")
End Sub