d12r9.frm

常用数值算法集哈

VERSION 5.00
Begin VB.Form Form1 
   Caption         =   "Form1"
   ClientHeight    =   6780
   ClientLeft      =   60
   ClientTop       =   345
   ClientWidth     =   6660
   LinkTopic       =   "Form1"
   ScaleHeight     =   6780
   ScaleWidth      =   6660
   StartUpPosition =   3  'Windows Default
   Begin VB.CommandButton Command1 
      Caption         =   "Command1"
      Height          =   375
      Left            =   4920
      TabIndex        =   0
      Top             =   6120
      Width           =   1215
   End
End
Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Private Sub Command1_Click()
    'PROGRAM D12R9
    'Driver for routine PZEXTR
    'Feed values from a rational function
    'Fn(x)=(1-x+x**3)/(x+1)**n
    NV = 4
    NUSE = 5
    Dim YEST(4), YZ(4), DY(4)
    For I = 1 To 10
        IEST = I
        XEST = 1# / CSng(I)
        DUM = 1# - XEST + XEST ^ 3
        For J = 1 To NV
            DUM = DUM / (XEST + 1#)
            YEST(J) = DUM
        Next J
        Call PZEXTR(IEST, XEST, YEST(), YZ(), DY(), NV, NUSE)
        Print
        Print Tab(5); "I= "; I
        Print Tab(5); "Extrap. Function: ";
        For J = 1 To NV
            Print Tab(15 + J * 12); Format(YZ(J), ".#####0");
        Next J
        Print Tab(5); "Estimated Error: ";
        For J = 1 To NV
            Print Tab(15 + J * 12); Format(DY(J), ".#####0");
        Next J
    Next I
    Print Tab(5); "Actual Values:    "; Tab(27); "1.000000";
    Print Tab(39); "1.000000"; Tab(51); "1.000000"; Tab(63); "1.000000"
End Sub
Sub PZEXTR(IEST, XEST, YEST(), YZ(), DY(), NV, NUSE)
    Static X(11), QCOL(10, 7)
    NCOL = 7
    NMAX = 10
    Dim D(10)
    X(IEST) = XEST
    For J = 1 To NV
        DY(J) = YEST(J)
        YZ(J) = YEST(J)
    Next J
    If IEST = 1 Then
        For J = 1 To NV
            QCOL(J, 1) = YEST(J)
        Next J
    Else
        M1 = IEST
        If IEST > NUSE Then M1 = NUSE
        For J = 1 To NV
            D(J) = YEST(J)
        Next J
        For K1 = 1 To M1 - 1
            DELTA = 1# / (X(IEST - K1) - XEST)
            F1 = XEST * DELTA
            F2 = X(IEST - K1) * DELTA
            For J = 1 To NV
                Q = QCOL(J, K1)
                QCOL(J, K1) = DY(J)
                DELTA = D(J) - Q
                DY(J) = F1 * DELTA
                D(J) = F2 * DELTA
                YZ(J) = YZ(J) + DY(J)
            Next J
        Next K1
        For J = 1 To NV
            QCOL(J, M1) = DY(J)
        Next J
    End If
    Erase D
End Sub