topic ...teaching maths to Archicad? in Modeling

...teaching maths to Archicad?

Anonymous — Tue, 15 Nov 2011 14:12:27 GMT

Hi everyone,
I'm trying to automate some calculations I need to do using AC13.

The calculation I need is very simple: gross zone volume.

So I created a list schedule, and asked AC to list zones by storey as in the attached screenshot.

Now, if you look at the values AC gives me, there must be an error somewhere:

AC calculation:

P0 volume: 92,79 m2 x 2,38 m = 215,35 m3

Good old calculator gives me instead:

P0 volume: 92,79 m2 x 2,38 m = 220,84 m3

I checked the BIM model one hurdred time but I cannot find the error. I know I must have set something wrong, but this is not the first time I have AC do this kind of calculations. It is definitely the first time I get such a big calculation error.
Does anyone have similar problems with calculations in AC?

Re: ...teaching maths to Archicad?

Steve Jepson — Tue, 15 Nov 2011 16:39:46 GMT

Did you check Calculation Rules for zones in Project Preferences ?

Unless I don't understand what the comma means in your dimensions, they don't add up to what you get anyway. ?

92.79m x 92.79m x 2.38m=20,491.76m3

Re: ...teaching maths to Archicad?

Anonymous — Tue, 15 Nov 2011 16:59:06 GMT

here's a screenshot of the calculation preferences.

even if the menu is in Italian, you can see I did not set any calculation rule for this project.

Re: ...teaching maths to Archicad?

Anonymous — Tue, 15 Nov 2011 17:00:53 GMT

..and the second screenshot

Re: ...teaching maths to Archicad?

Anonymous — Tue, 15 Nov 2011 20:33:16 GMT

Have you run update zones in the design menu?

Re: ...teaching maths to Archicad?

Anonymous — Wed, 16 Nov 2011 07:11:54 GMT

Yep, the zone is updated.

Furthermore, regardless from the zone update status, shouldn't the volume be calculated as Area x Height? This is the part I don't understand...

Re: ...teaching maths to Archicad?

Anonymous — Wed, 16 Nov 2011 07:51:54 GMT

...I found out that part of the zone volume is subtracted by a wall, see picture attached.

Re: ...teaching maths to Archicad?

Anonymous — Wed, 16 Nov 2011 07:52:52 GMT

It is weird, because I did not run any solid operation between the two elements

Re: ...teaching maths to Archicad?

Anonymous — Wed, 16 Nov 2011 07:53:45 GMT

also, the wall settings for "relations to zones" is set to "no relationship"

Re: ...teaching maths to Archicad?

Anonymous — Wed, 16 Nov 2011 07:54:52 GMT

how do I get rid of this interference, if it does not depend on the "relationship to zones" or on a solid element operation?

Re: ...teaching maths to Archicad?

Barry Kelly — Wed, 16 Nov 2011 08:16:05 GMT

Enrico wrote:
how do I get rid of this interference, if it does not depend on the "relationship to zones" or on a solid element operation?

What method are you using to place the zone?
Manual, inner edge or reference line?

How do the other walls fit around this zone?
i.e. what does it look like in plan.

Barry.

Re: ...teaching maths to Archicad?

Anonymous — Wed, 16 Nov 2011 08:39:22 GMT

I placed the zone manually, by drawing its polygon.

Re: ...teaching maths to Archicad?

Barry Kelly — Wed, 16 Nov 2011 09:01:06 GMT

If you have manually drawn the zone then I don't understand why it is trimming around the wall in 3D.

I assume that the 92.79m² matches the zone area exactly as it is drawn in plan.

If you delete the wall does it affect the 3D zone.

Clutching at staws here but move the zone away from the model and then see what the zone looks like in 3D. It will remain the same size if it is manually drawn.

Barry.

Re: ...teaching maths to Archicad?

Anonymous — Wed, 16 Nov 2011 09:26:19 GMT

Yes, 92,79 m2 is exactly the area of the zone. The ploygon I drew manually is a simple rectangle.

If I delete the wall, then AC gives me the correct volume value.

If I copy the zone somewhere else, then the automatic subtraction disappears.

All pieces of evidence show that the wall is the problem.

How can I tell AC to calculate the volume based on the gross area instead of the net area?

Re: ...teaching maths to Archicad?

Miha Nahtigal — Wed, 16 Nov 2011 16:29:03 GMT

Let me guess... is it complex (profile) wall?

I had the same problem and I think it's a bug in Archicad.

http://archicad-talk.graphisoft.com/viewtopic.php?p=184979

Re: ...teaching maths to Archicad?

Anonymous — Wed, 16 Nov 2011 16:41:03 GMT

nope. pretty boring standard wall...

but I guess the same bug must happen even for normal walls

Re: ...teaching maths to Archicad?

Steve Jepson — Wed, 16 Nov 2011 18:25:54 GMT

Not very likely but perhaps your zone stamp is not for the zone you think it is. ?
I downloaded your .pdf and put an area fill over the zone. The scale of the drawing is verified +/- by the door I added. The area is quite different from your zone area. ??

Re: ...teaching maths to Archicad?

Anonymous — Wed, 16 Nov 2011 19:24:08 GMT

...and the winner is.... VUEGO!

I double checked, and it must be a bug. I just moved the zone border from the wall reference line by only 1 mm, and AC calculated the volume properly.

So, it's a bug.

Thanks everyone for your help!

Enrico

(so, now what? we keep the bug, pay for the yearly update, and...?)

Re: ...teaching maths to Archicad?

Tom Krowka — Mon, 23 Apr 2012 23:59:39 GMT

I am interested in determining the volume of the zone minus the wall volumes. I tried to do it but have not been successful.

Re: ...teaching maths to Archicad?

Anonymous — Tue, 24 Apr 2012 05:45:45 GMT

Can you adapt the zone to the inner edge of the walls?

Otherwise, you can create an interactive schedule to calculate the volume of the zone and of the walls, and you do the math separately...