Apply a formula driven shared parameter to a system family [via API]

[Viveka_CD]

Posting this on behalf of customer @Arciviz  as a feature request

Customer wants to apply a formula driven shared parameter to a system family, (we can write a macro to try and achieve this) but currently, the API can be used to apply shared parameters to system families, but the ability to apply formulas is not supported, see https://knowledge.autodesk.com/search-result/caas/CloudHelp/cloudhelp/2016/ENU/Revit-API/files/GUID-.... 

Thanks,

[Viveka_CD]

@Arciviz please vote on this idea

[germanperales]

System families would be much more usable and configurable if the built-in parameters could be linked by formula to global parameters. Nowadays there are only a few parameters that can be linked to global parameters, with the only relationship of "equal". 

There are lots of built-in parameters that still are unable to be linked to global parameters. For example: layers inside a wall or floor.

[Chris_Baze]

This is currently the biggest limitation in Revit for us. Multi-category schedules cannot display basic information about the Width, Length, Height, and Perimeter of objects. We'd like to make our own "universal" perimeters to display this data, but currently need to run a Dynamo script to update values for the system families.