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Dimitri Harvalias
2007-06-27, 08:06 PM
Is there a way to deal with rounding errors in a schedule total?
Check the attached image. The individual room areas are rounded to one decimal place, as is the total. The problem is when you add the digits up for the decimal values they don't add up to the value displayed in the grand total.

I know the areas are correct but some people get worked up about the fact that Revit 'can't add' a simple column of numbers and they start to doubt the accuracy of the numbers.

Thanks

VinceFerrero
2007-06-28, 12:49 AM
This seems to be typical of CAD applications in general.

ACA2008 also has this problem with it's Spaces Tool (similar to Revit rooms). I've had an entire building Area Analysis plan dismissed because of it.

To rectify I had to display a ridiculous amount of decimal placings. Wish they would fix it.

Steve_Stafford
2007-06-28, 03:12 AM
cad in general, try life... our bank has a "keep the change" program where they round purchases up and down depending on the how close to a whole dollar they are. This means we have fun balancing our checking...but we've collected several hundred dollars in the process, at least it looks that way :confused:

We also have overall dimensions that don't "add" up correctly don't we?

Where such rounding is employed I'd state it with a disclaimer at the bottom/top or both so it is clear that the individuals are rounded and the total represents the accurate accounting of area.

We had a project where school rooms had to be a minimum area and we designed them slightly larger. We arrived at the same number for all but the end rooms where thicker wall construction reduced the size by a little bit but not less than the required minimum. The client objected to the difference and the PM blamed it on a computer glitch rather than explaining that the room is actually a little smaller in reality from a construction standpoint. The answer, we just want the tag to say the same number please. So room area accuracy...in whose eyes? :smile: Sorry no help...just blabbering...

Might be nice if we could tell the schedule totals to report the rounded total so the column(s) does add up eh?

Dimitri Harvalias
2007-06-28, 03:57 AM
Thanks guys. That's what I figured. The municpal authority that my client is dealing with seems to be just looking for an excuse to be a PITA. :beer:

dbaldacchino
2007-06-28, 01:24 PM
You could always use a shared parameter and type the area in manually ;) I'd only do that in case they're being a PITA. We always turn off areas on our final plans and just have occupancy numbers showing.

I have not played around with this, but am wondering if it's possible to create a calculated column that would round your area and make it an absolute number; then your totals should not have any variation. You would then hide the actual area column in your schedules and just use this calculated column.

aaronrumple
2007-06-28, 01:35 PM
...just increase the accuracy out to the square nanometer. Let the complainers do the rounding.

We had a project (school) where the classrooms were to be 800 sf. I had the rounding set to 2 decimal places. and the classroom was 800.25 sf. Only off by 34.56 sq. in. - or the size of standard envelope. The CM reviewer said no good - redesign. I reset the rounding to no decimals.

Lets face it - in construction if the contractor is within +/-1" - I'm thrilled.

rdaniel
2007-08-22, 09:39 PM
We always turn off areas on our final plans and just have occupancy numbers showing.

David,

How are you rounding up for occupancy loads? Ex. if the area is 110SF & and the occ. factor is 100, then the occupancy load is 1.1, but needs to round up to 2. Standard rounding in Revit would round it down to 1.

jtobin.68416
2007-08-23, 02:41 AM
One workaround that I use all the time is to add 0.49 to the occupancy calculation formula. (I think I got that tip on this newsgroup).
So my occupancy calc reads " (Area/Occupant Load Factor) + 0.49.
It seems crude but it works all the time, at least so far.

John Tobin

dbaldacchino
2007-08-23, 09:53 PM
That's exactly what I do and I also learned that technique a while back from these forums.

rdaniel
2007-08-23, 09:57 PM
Ah, another workaround, but at least it works. Thanks guys.

vgonzales
2008-08-25, 10:41 PM
For rounding up occupant loads, here is a screen shot of my occupant load symbol parameters.

Hope this helps you guys,

Leo

patricks
2008-08-26, 12:56 PM
I posted this thread awhile back about how to deal with rounding errors.

http://forums.augi.com/showthread.php?t=80094