2007-2010 年访问综述

Question

我需要在 Access 2007 中汇总到 2dp，并尝试使用此论坛上类似查询的答案，但发现除了一个之外的所有错误。有没有人有一个经过测试的 VB 脚本/函数，它可以接受一个小数点后 14 位长并输出到 2 dp 的值？

Answer 1

确实：

' Common constants.
'
' Base values.
Public Const Base2      As Double = 2
Public Const Base10     As Double = 10

' Enums.
'
Public Enum rmRoundingMethod
    Down = -1
    Midpoint = 0
    Up = 1
End Enum


' Rounds Value up with count of decimals as specified with parameter NumDigitsAfterDecimal.
'
' Rounds to integer if NumDigitsAfterDecimal is zero.
'
' Optionally, rounds negative values away from zero.
'
' Uses CDec() to prevent bit errors of reals.
'
' Execution time is about 0.5µs for rounding to integer,
' else about 1µs.
'
' 2018-02-09. Gustav Brock, Cactus Data ApS, CPH.
'
Public Function RoundUp( _
    ByVal Value As Variant, _
    Optional ByVal NumDigitsAfterDecimal As Long, _
    Optional ByVal RoundingAwayFromZero As Boolean) _
    As Variant

    Dim Scaling     As Variant
    Dim ScaledValue As Variant
    Dim ReturnValue As Variant

    ' Only round if Value is numeric and ReturnValue can be different from zero.
    If Not IsNumeric(Value) Then
        ' Nothing to do.
        ReturnValue = Null
    ElseIf Value = 0 Then
        ' Nothing to round.
        ' Return Value as is.
        ReturnValue = Value
    Else
        If NumDigitsAfterDecimal <> 0 Then
            Scaling = CDec(Base10 ^ NumDigitsAfterDecimal)
        Else
            Scaling = 1
        End If
        If Scaling = 0 Then
            ' A very large value for NumDigitsAfterDecimal has minimized scaling.
            ' Return Value as is.
            ReturnValue = Value
        ElseIf RoundingAwayFromZero = False Or Value > 0 Then
            ' Round numeric value up.
            If Scaling = 1 Then
                ' Integer rounding.
                ReturnValue = -Int(-Value)
            Else
                ' First try with conversion to Decimal to avoid bit errors for some reals like 32.675.
                On Error Resume Next
                ScaledValue = -Int(CDec(-Value) * Scaling)
                ReturnValue = ScaledValue / Scaling
                If Err.Number <> 0 Then
                    ' Decimal overflow.
                    ' Round Value without conversion to Decimal.
                    ScaledValue = -Int(-Value * Scaling)
                    ReturnValue = ScaledValue / Scaling
                End If
            End If
        Else
            ' Round absolute value up.
            If Scaling = 1 Then
                ' Integer rounding.
                ReturnValue = Int(Value)
            Else
                ' First try with conversion to Decimal to avoid bit errors for some reals like 32.675.
                On Error Resume Next
                ScaledValue = Int(CDec(Value) * Scaling)
                ReturnValue = ScaledValue / Scaling
                If Err.Number <> 0 Then
                    ' Decimal overflow.
                    ' Round Value without conversion to Decimal.
                    ScaledValue = Int(Value * Scaling)
                    ReturnValue = ScaledValue / Scaling
                End If
            End If
        End If
        If Err.Number <> 0 Then
            ' Rounding failed because values are near one of the boundaries of type Double.
            ' Return value as is.
            ReturnValue = Value
        End If
    End If

    RoundUp = ReturnValue

End Function

示例：

Value14 = CDec("12345.00000000000001")
Value02 = RoundUp(Value14, 2) 
Value02 -> 12345.01 

您也可以研究我关于以极高的精度进行舍入的文章：

Rounding values up, down, by 4/5, or to significant figures

（如果您没有帐户，请浏览链接：阅读全文）

完整代码也在 GitHub 上：VBA.Round