Is there a limit on the length of Lists?

I’ve got a graph that worked on smaller projects, but just blew up on a big project.

This graph worked OK on a smaller project, but of a big one, I got the error mentioned below.

By “big”, I mean this project had over 1600 doors. What I’m wondering is if there’s a limit on the length of lists & it just couldn’t handle 1600.

My other question is: How do I figure out which one of the 1600 entries in the list is the one causing the error?












Here’s what I filed on GitHub:

My graph selects all Doors in a project, then gets the nearby Rooms
Next it compares the Door Number to both Room Numbers and sets a flag if the Door matches one of the Rooms or false if it matches neither.

What did you expect to see?

This has worked on small projects, but on a large project with I got an error: <strong style="font-weight: bold;">Internal error: please report: Dereferencing a non-pointer (3f47aacd)

This was in an Element.GetParameterValueByName node


There is a limit on the length of lists but it is much much more than 1600. Try using your custom node together with a node and then check the resulting list for null values.

As Dimitar says, there might be a limit, but 1600 shouldnt be a problem

My experience is that a list with hundreds of thusands of list entries is not a problem. In the below, there were around 30,000 objects each with say 8 parameters so the initial list was well into the hundreds of thusands.

I have found there is a definite ‘hard’ limit where Dynamo will hang and no amount of processing time will matter







hi @Andrew_Hannell
i had once list of 75,000 elements and that was no problem except the performance.