d16r1.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 D16R1
    'Driver for routine SOR
    JMAX = 11
    PI = 3.1415926
    Dim A(11, 11), B(11, 11), C(11, 11), D(11, 11)
    Dim E(11, 11), F(11, 11), U(11, 11)
    For I = 1 To JMAX
        For J = 1 To JMAX
            A(I, J) = 1#
            B(I, J) = 1#
            C(I, J) = 1#
            D(I, J) = 1#
            E(I, J) = -4#
            F(I, J) = 0#
            U(I, J) = 0#
        Next J
    Next I
    MIDL = JMAX / 2 + 1
    F(MIDL, MIDL) = 2#
    RJAC = Cos(PI / JMAX)
    Call SOR(A(), B(), C(), D(), E(), F(), U(), JMAX, RJAC)
    Print
    Print Tab(5); "SOR Solution:"
    Print
    For I = 1 To JMAX
        For J = 1 To JMAX
            Print Tab(5 + (J - 1) * 8); Format$(U(I, J), "#.#0");
        Next J
    Next I
    Print Tab(5)
    Print Tab(5); "Test that sulotion satisfies Difference Eqns:"
    Print
    For I = 2 To JMAX - 1
      For J = 2 To JMAX - 1
        AAA = U(I + 1, J) + U(I - 1, J) + U(I, J + 1) + U(I, J - 1)
        F(I, J) = AAA - 4# * U(I, J)
      Next J
      For J = 2 To JMAX - 1
        Print Tab(5 + (J - 2) * 8); Format$(F(I, J), "#.#0");
      Next J
    Next I
End Sub