VB 方差 的计算公式

来源：百度知道 编辑：UC知道 时间：2024/06/06 12:59:14
目的：方便求数据的方差

其中text1-text20分别为输入框，label1为显示框。按钮一：求平均数。按钮二求方差
请注意不要再找百度的一些答案

何必弄那么多个Textbox,给你写个界面简洁的，建一个Text1，为数据录入与结果的显示，建两个按钮，一个算平均数，一个算方差，代码如下：
Dim a() As Single
Dim n As Integer
Dim s As Single

Private Sub Command1_Click()
Dim av As Single
av = s / n
Text1 = av
End Sub

Private Sub Command2_Click()
Dim av As Single, result As Single
av = s / n
Text1 = av
For i = 1 To n
result = result + (a(i) - av) ^ 2
Next
Text1 = result / n
End Sub

Private Sub Form_Load()
Text1.Text = ""
Command1.Caption = "求平均数(&A)"
Command2.Caption = "求方差(&Q)"
End Sub

Private Sub Text1_KeyPress(KeyAscii As Integer)
If KeyAscii = 13 Then
If Text1.Text <> "" Then
n = n + 1
ReDim Preserve a(1 To n)
a(n) = Text1
s = s + a(n)
Text1.Text = ""
Text1.SetFocus
Else
MsgBox "请输入数据"
End If
End If
End Sub

dim a(10) as double