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cbaze
2009-09-23, 09:00 PM
I am trying to make a Nanawall family because the ones they provide are worthless (paramerters do not work). I am getting the message "Could not get variable value", see attached image. What am I doing wrong?

sthedens
2009-09-23, 09:27 PM
The first time I tried replicating your problem I got the same error. I clicked OK and it calculated a value for Panel Width. Every attempt at replicating the error has failed:

1. Re-entered the formula - no error.
2. Deleted both parameters, recreated them, entered formula - no error.
3. Started new family... entered formula - no error.
4. Closed Revit, Opened Revit... entered formula - no error.

cbaze
2009-09-23, 09:36 PM
I still can't make it work. Do you have No. of Panels set as integer and Panel Width set as length?

patricks
2009-09-23, 09:37 PM
Well... where is the Width parameter? Is it up above and just not shown in your screen cap?

cbaze
2009-09-23, 09:38 PM
Door family

cbaze
2009-09-23, 09:42 PM
ah ha! I hadn't assigned the width parameter to anything yet (I thought I had because I have a nested frame family in the model. Thanks guys.

patricks
2009-09-23, 09:45 PM
Well I got it to work, using a Width (Length), Panel Width (Length), and No. of Panels (Integer) parameter. However I'm not sure if the result is what is intended. I'm assuming the Width parameter is the overall door Width built-in parameter, correct? Then you have number of panels. Is the Panel Width parameter supposed to be the width of all the panels, or the width of each individual panel?

If the latter, then you need to add some more parenthesis in there to get the order of operations correct. Right now it's taking the 3/4" and dividing it by the number of panels first, and then that is subtracted from the Width parameter. This is standard mathematical order of operations: 1. Bracketed expressions 2. Parenthetical expressions 3. Multiply or divide 4. Add or subtract.

You need to put parenthesis around the Width - 3/4" portion if you want the Panel Width to be the width of each individual panel.

cbaze
2009-09-23, 11:50 PM
Thanks, I also had the gap multipllier in the wrong place. The intent was to put a 3/8" gap between each panel and the frame. The correct formula is (Width - 0' 0 3/4" - ((No. of Panels - 1) * 0' 0 3/8")) / No. of Panels