[AccessD] A2K - Adding decimal error

Hi Charlotte

It fails all right, but not you have to go beyond 16 mio.:

Public Sub TestSingle()

  Dim sng As Single
  Dim lng As Long
  
  For lng = 0 To 100000000
    If lng <> sng Then Exit For
    sng = sng + 1
  Next
  Debug.Print lng, sng

End Sub

It runs to:
 16777217      1.677722E+07 

/gustav

>>> cfoust at infostatsystems.com 04/27 7:17 pm >>>
I've seen it with addition as well.  You can build a test in code and
loop multiple times adding 1 to the integer of a floating point and
testing the mod to see if there is a remainder.  Believe me, it will
occur.

Charlotte Foust


-----Original Message-----
From: Gustav Brock [mailto:Gustav at cactus.dk] 
Sent: Wednesday, April 27, 2005 9:37 AM
To: accessd at databaseadvisors.com 
Subject: RE: [AccessD] A2K - Adding decimal error


Hi Reuben

Charlotte a guy? You better be careful!

You mostly see this with subtraction (which includes addition of
negative values); I've never seen it with addition of positives.

If you can't change the source data type be sure to wrap the values in
CCur(). If you need more than the four decimals of Currency you may
choose Double but round the results whenever possible.

/gustav

>>> reuben at gfconsultants.com 04/27 6:26 pm >>>
You guys nailed that one.  HoursWorked is a single.  I never
considered
it would cause a problem with addition.  Of course, after all the work
I
did on payroll calculations I can't beleive it was still a single.

Thanks.

Reuben Cummings
GFC, LLC
phone: 812.523.1017
email: reuben at gfconsultants.com 


-----Original Message-----
From: accessd-bounces at databaseadvisors.com 
[mailto:accessd-bounces at databaseadvisors.com]On Behalf Of Gustav Brock
Sent: Wednesday, April 27, 2005 10:53 AM
To: accessd at databaseadvisors.com 
Subject: Re: [AccessD] A2K - Adding decimal error


Hi Reuben

He is probably adding and subtraction 0.1 hour as well and you are
using
data type Single for that. Change to data type Currency ...

/gustav

>>> reuben at gfconsultants.com 04/27 5:38 pm >>>
A client came across this for me...

One employee has 10 pay records on one day that are each .6 hours.
After
gathering all the pay info I use a standard grouping query with a sum
to
get the total hours.

Rather than adding up to 6 hours, these 10 records resolve to
6.00000023841858

Why the strange decimals?

Thanks.

Reuben Cummings
GFC, LLC
phone: 812.523.1017
email: reuben at gfconsultants.com