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A better rounding function

• • Reply

  10 years ago

  by Developer Fusion Bot

  Developer Fusion Bot

  , United Kingdom

  Joined 2 years ago

  This thread is for discussions of A better rounding function.

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• • Reply

  4 years ago

  by tsutommy

  tsutommy

  , United States

  Joined 4 years ago

  This current function fails for some decimal values.  A -.99 which would round to -1, rounds to 0 with the current code.  Sorry, I can't remember the other issue I had with it but my fixes below took care of both my problems.
  

  
     Public Function RoundAdv(ByVal dVal As Double, Optional ByVal iPrecision As Integer = 0) As Double
         Dim roundStr As String
         Dim WholeNumberPart As String
         Dim DecimalPart As String
         Dim i As Integer
         Dim RoundUpValue As Double
         Dim negative As Boolean
         roundStr = CStr(dVal)
  

  
             If InStr(1, roundStr, ".") = 0 Then
                 RoundAdv = dVal
                 Exit Function
             End If
             If dVal < 0 Then
                 negative = True
             End If
             WholeNumberPart = Mid$(roundStr, 1, InStr(1, roundStr, ".") - 1)
             DecimalPart = Mid$(roundStr, (InStr(1, roundStr, ".")))
             If Len(DecimalPart) > iPrecision + 1 Then
                 Select Case Mid$(DecimalPart, iPrecision + 2, 1)
                     Case "0", "1", "2", "3", "4"
                         DecimalPart = Mid$(DecimalPart, 1, iPrecision + 1)
                     Case "5", "6", "7", "8", "9"
                         RoundUpValue = 0.1
                         For i = 1 To iPrecision - 1
                             RoundUpValue = RoundUpValue * 0.1
                         Next
                         DecimalPart = CStr(Val(Mid$(DecimalPart, 1, iPrecision + 1)) + RoundUpValue)
                         If Mid$(DecimalPart, 1, 1) <> "1" Then
                             DecimalPart = Mid$(DecimalPart, 2)
                         Else
                             If negative Then
                                 WholeNumberPart = CStr(Val(WholeNumberPart) - 1)
                             Else
                                 WholeNumberPart = CStr(Val(WholeNumberPart) + 1)
                             End If
                             DecimalPart = ""
                         End If
                 End Select
             End If
             RoundAdv = Val(WholeNumberPart & DecimalPart)
             If RoundAdv <> 0 Then
                 If negative And RoundAdv > 0 Then
                     RoundAdv = -1 * RoundAdv
                 End If
             End If

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• • Reply

  1 year ago

  by NongOil

  NongOil

  , Thailand

  Joined 1 year ago

  Please try this

  Public Function RoundAdv(ByVal Number As Variant, Optional lDigit As Long = 0) As Double
      
     If Not IsNumeric(Number) Then Exit Function
     RoundAdv = Round(CDbl(Number) + (IIf(Number < 0, -1, 1) / (10 * (10 ^ lDigit))), lDigit)
  
  
  

  End Function
  
  

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