VB实现的龙格库塔算法及其应用

计算机仿真（龙格库塔方法）的软件VB设计与实现

Dim a(0 To 10) As Single, b(0 To 10) As Single, c(0 To 10) As Single, d(0 To 10) As Single
Dim e(0 To 10) As Single, h(0 To 10) As Single, p(0 To 10) As Single, q(0 To 10) As Single
Dim n1 As Byte, n2 As Byte                                            'n1表示的是y的阶数,n2表示的是输入函数的阶数
Dim i As Integer
Dim f(0 To 2000) As Single                                   'f(m)=y,也就是各个时刻的y值
Dim X0(0 To 12) As Single, X1(0 To 12) As Single
Dim dt As Single, u As Single                                'dt为采样周期,u为输入
Dim q1 As Single, p1 As Single, h1 As Single, e1 As Single
Dim b0(0 To 10) As Single, bn(-4 To 10) As Single
Dim m As Integer
Dim max As Single



Private Sub Combo1_Click()
  n1 = Combo1.ListIndex + 1            'n1表示的是y的阶数
  
  For i = n1 + 1 To 8
    Text1(i).Visible = False
    Label1(i).Visible = False
    Label9(i).Visible = False
  Next
  For i = 0 To n1
    Text1(i).Visible = True
    Label1(i).Visible = True
    Label9(i).Visible = True
  Next
  

  Combo2.Clear
  Combo2.Text = "请选择输出u的最大阶数"
  For i = 0 To n1
    Combo2.AddItem ((i) & "阶")
  Next
  
End Sub

Private Sub Combo2_Click()
  n2 = Combo2.ListIndex                    'n2表示的是输入函数的阶数
  For i = n2 + 1 To 8
    Text2(i).Visible = False
    Label2(i).Visible = False
    Label10(i).Visible = False
  Next
  For i = 0 To n2
    Text2(i).Visible = True
    Label2(i).Visible = True
    Label10(i).Visible = True
  Next
  
End Sub


Private Sub Calculate_Click()

dt = Val(Text3.Text)                         'dt是采样周期
u = Val(Text4.Text)
n1 = Combo1.ListIndex + 1
If n1 = 0 Then                                     '对付忘记选择最高阶数时的情况