Generative Design Previews Blank and Output Value Zeroing Out - What's Wrong?

I have re-worked an old Dynamo script to be geared for Generative Design. It functions correctly in the Dynamo interface, and populates an appropriate output value, but I get blank previews and a zero-value output for all generations on the Explore Outcomes window when run through generative design. What I’ve tried: checked for updates to Dynamo and Revit, removed all custom nodes from the script with exception to the Generative design Data Gate node, pushed all Revit-related queries and nodes to after data gate to avoid any required Data.remember nodes, and have tried freezing all non-essential nodes to the generative portion of the script - and still no luck.

Check to make sure you don’t get all null values and empty geometry in a cross product study of 3 values for each variable. This will ensure that GD hasn’t just stumbled into a series of ‘well performing edge conditions (by way of nulls reading as 0’s).

If that doesn’t work, open the graph in Dynamo Sandbox, and see if you get any results when you run the graph. If not, then replace the nodes between your remember node and your data.Gate node (including anything associated with geometry and evaluation) with code that doesn’t require the Revit API.

Jacob, thanks for the tips! It was indeed a couple of lingering Revit transactional nodes that I looked over. Looking at it in Sandbox was a huge help. Looks like it’s all functioning now, minus the logic related items that I need to fix for good outcome reporting.

Thanks again!

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