Sheet Renumbering Definition: Returning an Error

Hello Everyone,

I’m trying to create a seemingly simple definition that will renumber a list of sheets. I followed a tutorial on Youtube and created the exact same definition, however it won’t work for me. The definition is returning the error “Dereferencing a non-pointer”. I’m very new to Dyanmo (I have a solid understanding of Grasshopper and made the mistake in thinking Dynamo is similar) so I’m not so great at trouble shooting.

Please Help!

What does your list of elements look like?

show us a complete picture of the graph
like Nick Martin i think that youre input in element of youre node ElementSetParameterName is not a Element (sheet)
Ps with renumbering sheets it is better to first run a test run. For example add test before the sheet names and run the graph again with the right sheet name. Because of the possibility of problems with duplicate sheet names in revit

Sorry for the delayed response. I renumbered the sheets so there shouldn’t be any conflict in sheet numbers or names. I attached a view of the complete graph as well.

Thank you!


You don’t have any elements going into your Element.SetParameterByName node. It looks like your sliced list, which is just strings, is going in instead. Get your sorted list of sheet elements and plug that in.

I plugged in the right node it all works.
Thank you!

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