rounding in access

[ziccardi]

I have a number 6.51495989352464 that I need to round to 6.51

I am using the following code:
Public Function MyRound(dblInput As Currency, intDecimal As Integer) As Double

If dblInput < 0 Then
MyRound = -Int(CDec((Abs(dblInput) * 10 ^ intDecimal) + 0.5)) / 10 ^ intDecimal
Else
MyRound = Int(CDec((dblInput * 10 ^ intDecimal) + 0.5)) / 10 ^ intDecimal
End If


End Function

When I step into the code what is actually going through the MyRound code is 6.515 so it makes sense that it is rounding to 6.52 but I do not know why it is rounding from 6.51495989352464 to 6.515.

It's probably very simple but I'm not seeing it.

[ziccardi]

one other wierd quirk: for some reason the code is multiplying
( 210.16 ) * ( 3.09999994933605E-02 )
it should be multiplying
( 210.16 ) * ( 0.0310)

I know it's not much of a difference but the 0.0310 is being pulled directly from a table where the field is defined as Number-Single-Fixed (4 decimal places)

Thanks!

[gershwyn]

Have you tried using the built in round function?

Round(6.51495989352464, 2)

=6.51

[ziccardi]

The built in round function in Access uses Banker' Rounding logic. Banker's rounding rounds .5 up sometimes and down sometimes.

I need it to be Symmetric arithmetic rounding where it rounds .5 away from 0. Similar to Excel Worksheet Round function.

Besides it seems to be rounding correctly but it looks like the number is being rounded before it even gets to my rounding code. I am going to try changing dblInput to Double in the code and see if that corrects it.

[ADezii]

The result that I am getting is 6.52, namely:

Public Function MyRound(dblInput As Currency, intDecimal As Integer) As Double
  If dblInput < 0 Then
    MyRound = -Int(CDec(Abs(dblInput) * (10 ^ intDecimal)) + 0.5) / (10 ^ intDecimal)
  Else
    MyRound = Int(CDec(dblInput * (10 ^ intDecimal)) + 0.5) / (10 ^ intDecimal)
  End If
End Function

Debug.Print MyRound(6.51495989352464 ,2)

OUTPUT:

6.52

[ziccardi]

I changed dblInput As Currency to dblInput As Double ... it seems to work now