modxzx.bas

用于空间插值的地理数据处理的趋势面分析

Attribute VB_Name = "ModXZX"
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'模块名：ModXZX 置信度0.05水平
'函数名：XZX
'功能：检验趋势面的变异的显著性
'参数：n－integer型变量，观测点数
        'p－integer型变量，多项式趋势面的项数，不包括常熟项
        'Sreg－double型变量，反映拟合度有利部分
        'Sres－double型变量，放映拟合度不利部分
'返回值：XZX －double型变量，返回变异性常数

Public Function XZX(ByVal n As Integer, ByVal p As Integer, ByVal Sreg As Double, ByVal Sres As Double) As Double
    Dim F As Double
    Dim n2 As Integer
    Dim Z As Double
    n2 = n - p - 1
    Z = (Sreg / p) / (Sres / (n - p - 1))
    
    If n2 > 4 And n2 <= 10 Then
        F = F1 + ((F2 - F1) / 6) * (n2 - 4)
    ElseIf n2 > 10 And n2 <= 15 Then
        F = F2 + ((F3 - F2) / 5) * (n2 - 10)
    ElseIf n2 > 15 And n2 <= 20 Then
        F = F3 + ((F4 - F3) / 5) * (n2 - 15)
    ElseIf n2 > 20 And n2 <= 25 Then
        F = F4 + ((F5 - F4) / 5) * (n2 - 20)
    ElseIf n2 > 25 And n2 <= 30 Then
        F = F5 + ((F6 - F5) / 5) * (n2 - 25)
    ElseIf n2 > 30 And n2 <= 40 Then
        F = F6 + ((F7 - F6) / 10) * (n2 - 30)
    ElseIf n2 > 40 And n2 <= 60 Then
        F = F7 + ((F8 - F7) / 10) * (n2 - 40)
    ElseIf n2 > 60 And n2 <= 120 Then
        F = F8 + ((F9 - F8) / 60) * (n2 - 60)
    ElseIf n2 > 120 Then
        F = F10
    Else
        F = F1
    End If
    
    If X > F Then
        XZX = F
    Else
        MsgBox "趋势面变异不显著"
    End If
End Function