d11r3.txt

常用的数值算法的VB程序

Private Sub Command1_Click()
    'PROGRAM D11R3
    'Driver for routine BRENT
    TOL = 0.000001
    EQL = 0.0001
    Dim AMIN(20)
    NMIN = 0
    Print
    Print Tab(5); "Minima of the function BESSJ0"
    Print
    Print Tab(3); "Min. #          X          BESSJ0(X)     BESSJ1(X)"
    For I = 1 To 100
        AX = I
        BX = I + 1#
        Call MNBRAK(AX, BX, CX, FA, FB, FC)
        B = BRENT(AX, BX, CX, TOL, XMIN)
        If NMIN = 0 Then
            AMIN(1) = XMIN
            NMIN = 1
            Print Tab(5); Format$(NMIN, "##");
            Print Tab(15); Format$(XMIN, "##.#####0");
            Print Tab(29); Format$(BESSJ0(XMIN), "##.#####0");
            Print Tab(43); Format$(BESSJ1(XMIN), "##.#####0")
        Else
            IFLAG = 0
            For J = 1 To NMIN
                If Abs(XMIN - AMIN(J)) <= EQL * XMIN Then IFLAG = 1
            Next J
            If IFLAG = 0 Then
                NMIN = NMIN + 1
                AMIN(NMIN) = XMIN
                Print Tab(5); Format$(NMIN, "##");
                Print Tab(15); Format$(XMIN, "##.#####0");
                Print Tab(29); Format$(BESSJ0(XMIN), "##.#####0");
                Print Tab(43); Format$(BESSJ1(XMIN), "##.#####0")
            End If
        End If
    Next I
End Sub
Function FUNC(X)
    FUNC = BESSJ0(X)
End Function