sidel.frm

大学里必学的一门课程

VERSION 5.00
Begin VB.Form Form1 
   Caption         =   "Form1"
   ClientHeight    =   4725
   ClientLeft      =   45
   ClientTop       =   435
   ClientWidth     =   5115
   LinkTopic       =   "Form1"
   ScaleHeight     =   4725
   ScaleWidth      =   5115
   StartUpPosition =   3  '窗口缺省
   Begin VB.TextBox Text5 
      Height          =   264
      Left            =   1440
      TabIndex        =   9
      Top             =   960
      Width           =   972
   End
   Begin VB.CommandButton Command1 
      Caption         =   "执行"
      Height          =   2052
      Left            =   3600
      TabIndex        =   4
      Top             =   1080
      Width           =   252
   End
   Begin VB.TextBox Text4 
      Height          =   372
      Left            =   1440
      TabIndex        =   3
      Top             =   2760
      Width           =   1932
   End
   Begin VB.TextBox Text3 
      Height          =   372
      Left            =   1440
      TabIndex        =   2
      Top             =   2280
      Width           =   1932
   End
   Begin VB.TextBox Text2 
      Height          =   372
      Left            =   1440
      TabIndex        =   1
      Top             =   1800
      Width           =   1932
   End
   Begin VB.TextBox Text1 
      Height          =   372
      Left            =   1440
      TabIndex        =   0
      Top             =   1320
      Width           =   1932
   End
   Begin VB.Label Label5 
      Caption         =   "k ="
      Height          =   255
      Left            =   840
      TabIndex        =   10
      Top             =   960
      Width           =   495
   End
   Begin VB.Label Label4 
      Caption         =   "x4"
      Height          =   375
      Left            =   840
      TabIndex        =   8
      Top             =   2760
      Width           =   495
   End
   Begin VB.Label Label3 
      Caption         =   "x3"
      Height          =   375
      Left            =   840
      TabIndex        =   7
      Top             =   2280
      Width           =   495
   End
   Begin VB.Label Label2 
      Caption         =   "x2"
      Height          =   375
      Left            =   840
      TabIndex        =   6
      Top             =   1800
      Width           =   495
   End
   Begin VB.Label Label1 
      Caption         =   "x1"
      Height          =   375
      Left            =   840
      TabIndex        =   5
      Top             =   1320
      Width           =   375
   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 k As Integer
Dim n As Integer, i As Integer, j As Integer, a(4, 4) As Integer, b(4) As Integer
Dim x(1, 4) As Double, q(4) As Double, esp As Double, sum As Double
a(1, 1) = 2: a(1, 2) = -1: a(1, 3) = 0: a(1, 4) = 0: b(1) = 1
a(2, 1) = -1: a(2, 2) = 2: a(2, 3) = -1: a(2, 4) = 0: b(2) = 0
a(3, 1) = 0: a(3, 2) = -1: a(3, 3) = 2: a(3, 4) = -1: b(3) = 1
a(4, 1) = 0: a(4, 2) = 0: a(4, 3) = -1: a(4, 4) = 2: b(4) = 0
x(0, 1) = 1
x(0, 2) = 2
x(0, 3) = 3
x(0, 4) = 4

eps = 0.00003
n = 2000
For k = 1 To n
 For i = 1 To 4
    sum = 0
    For j = 1 To 4
      If j < i Then sum = sum + a(i, j) * x(1, j)
      If j > i Then sum = sum + a(i, j) * x(0, j)
       
    Next j
       x(1, i) = (b(i) - sum) / a(i, i)
       q(i) = x(1, i) - x(0, i)
 Next i

For i = 1 To 4
  If Abs(q(i)) > eps Then Exit For
Next i
    If i < 5 Then
       For j = 1 To 4
           x(0, j) = x(1, j)
       Next j
       
    
    Else
      
     Text1.Text = x(1, 1)
     Text2.Text = x(1, 2)
     Text3.Text = x(1, 3)
     Text4.Text = x(1, 4)
     Text5.Text = k
      Exit For
     End If
Next k
'If k = 100 Then Text6.Text = k

End Sub