form1.frm

计算方法的VB程序

VERSION 5.00
Begin VB.Form Form1 
   Caption         =   "Form1"
   ClientHeight    =   3195
   ClientLeft      =   60
   ClientTop       =   345
   ClientWidth     =   4680
   LinkTopic       =   "Form1"
   ScaleHeight     =   3195
   ScaleWidth      =   4680
   StartUpPosition =   3  '窗口缺省
   Begin VB.CommandButton Command3 
      Caption         =   "About"
      Height          =   375
      Left            =   0
      TabIndex        =   5
      Top             =   2640
      Width           =   735
   End
   Begin VB.CommandButton Command2 
      Caption         =   "End"
      Height          =   375
      Left            =   0
      TabIndex        =   4
      Top             =   2280
      Width           =   735
   End
   Begin VB.CommandButton Command1 
      Caption         =   "Ok"
      Height          =   735
      Left            =   720
      TabIndex        =   3
      Top             =   2280
      Width           =   735
   End
   Begin VB.TextBox Text3 
      Height          =   735
      Left            =   2760
      TabIndex        =   2
      Text            =   "2.5"
      Top             =   2400
      Width           =   1935
   End
   Begin VB.TextBox Text2 
      Height          =   1095
      Left            =   0
      TabIndex        =   1
      Text            =   "1,4,9,16;"
      Top             =   1080
      Width           =   2415
   End
   Begin VB.TextBox Text1 
      Height          =   1095
      Left            =   2040
      TabIndex        =   0
      Text            =   "1,2,3,4;"
      Top             =   0
      Width           =   2535
   End
   Begin VB.Label Label3 
      Caption         =   "请输入待计算值x"
      BeginProperty Font 
         Name            =   "楷体_GB2312"
         Size            =   14.25
         Charset         =   134
         Weight          =   400
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   735
      Left            =   1560
      TabIndex        =   8
      Top             =   2400
      Width           =   1215
   End
   Begin VB.Label Label2 
      Caption         =   "节点y坐标的值请输入到左边的输入框中"
      BeginProperty Font 
         Name            =   "楷体_GB2312"
         Size            =   14.25
         Charset         =   134
         Weight          =   400
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   1095
      Left            =   2520
      TabIndex        =   7
      Top             =   1200
      Width           =   2175
   End
   Begin VB.Label Label1 
      Caption         =   "  节点x坐标的值请输入到右边的输入框中"
      BeginProperty Font 
         Name            =   "楷体_GB2312"
         Size            =   14.25
         Charset         =   134
         Weight          =   400
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   1095
      Left            =   0
      TabIndex        =   6
      Top             =   0
      Width           =   2055
   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()
Dim t1, t2 As Date
t1 = Time
forward = 0
backward = 0
w = 0
With Text1
l = Len(.Text)
For i = 1 To l
If Mid(.Text, i, 1) = "," Or Mid(.Text, i, 1) = ";" Then
forward = i
x(w) = CInt(Mid(.Text, backward + 1, forward - backward - 1))
w = w + 1
backward = forward
End If
Next
End With
forward = 0
backward = 0
w = 0
With Text2
l = Len(.Text)
For i = 1 To l
If Mid(.Text, i, 1) = "," Or Mid(.Text, i, 1) = ";" Then
forward = i
y(w) = CInt(Mid(.Text, backward + 1, forward - backward - 1))
w = w + 1
backward = forward
End If
Next
End With
x0 = CDbl(Text3.Text)
w = w - 1
Call lagrange
t2 = Time
tm = CDbl(t2 - t1) * 24 * 3600
Form1.Hide
Form2.Show
End Sub
Private Sub lagrange()
Dim j, k As Integer
Dim z As Double
Debug.Print x0
y0 = 0
For k = 0 To w
z = y(k)
For j = 0 To w
If (j <> k) Then
 z = z * (x0 - x(j)) / (x(k) - x(j))
End If
Next j
y0 = z + y0
Next k
End Sub