RiR: how does "Parameter Formula" works?

Rhino.Inside Revit
1

Hello,

Does anyone knows or can put an example of how the “Parameter Formula” works?
I always get “null”, using parameters that have formulas, imposing formulas…

image
image1301×539 56.2 KB

I can´t find any tutorial or explanation or example. Just this explanation:
Use formulas in dimensions and parameters to drive and control parametric content in a model. The Parameter Formula component can be used to create Parameter Formulas using the syntax as covered in the Valid Formula Syntax and Abbreviations

Could anyone please provide an example? one screenshoot? explanation? or link to a tutorial if you know any.

Thanks,
Adria Marco

2

Like the autodesk documentation mentions they are found in the Family Editor and are Text based.

image
image2648×829 214 KB

3

So it cannot be “read” or “edited” from outside the family?
for example, I have a family with a formula parameter:

image
image1750×526 61.7 KB

When I do your script inside the family, it works as your screenshoot. But if I read the parameters from a project, selecting the element and reading the type parameters, I get “.null”

My goal is: I have arround 80 different generic families in the project, created with GH. I want to have a parameter formula on them. Is there a fest way t do it? Because now it looks like I should go inside each of the 80 families and run the script.

For example, “bought volume” = Volume * 1.1

Or maybe, have the Formula parameter as a Instance parameter?

Thanks,

4

Since these are being created in Grasshopper would creating a new template file with your Parameter Formula work? If not i believe there is a script posted where someone iterated through families as a family doc.