Access VBA自定義函數(shù)stdevp

STDEVP 是用來計(jì)算標(biāo)準(zhǔn)差的函數(shù),STDEV是樣本標(biāo)準(zhǔn)差的函數(shù),STDEVP是總體標(biāo)準(zhǔn)差的函數(shù)。

在Sql語(yǔ)句中 access可使用 STDEVP標(biāo)準(zhǔn)差的函數(shù)

但在VBA代碼中，如果對(duì)一組數(shù)字求標(biāo)準(zhǔn)差，則沒有一個(gè)自定義的函數(shù)，所以寫了一個(gè)STDEVP自定義函數(shù)

需要先創(chuàng)建一個(gè)臨時(shí)表 tblTmp 里面只有一個(gè)字段 FNum  類型為數(shù)字（雙精度型）

Public Function Stdevp(dblNum1 As Variant, Optional dblNum2 As Variant, Optional dblNum3 As Variant, Optional dblNum4 As Variant, Optional dblNum5 As Variant)

Dim rs As Object
CurrentDb.Execute "Delete * from tblTmp"
Set rs = CurrentDb.OpenRecordset("Select * from tblTmp")
rs.AddNew
rs("FNum") = dblNum1
rs.Update

If Not IsMissing(dblNum2) Then
rs.AddNew
rs("FNum") = dblNum2
rs.Update
End If

If Not IsMissing(dblNum3) Then
rs.AddNew
rs("FNum") = dblNum3
rs.Update
End If


If Not IsMissing(dblNum4) Then
rs.AddNew
rs("FNum") = dblNum4
rs.Update
End If


If Not IsMissing(dblNum5) Then
rs.AddNew
rs("FNum") = dblNum5
rs.Update
End If

Stdevp = Nz(DStDevP("FNum", "tblTmp"))


End Function