Problem with If function

First list works correctly

but second one and next not

I can’t extract each list because it is depend of situation and I don’t know how many sublist will be.
Do you know the reason, or maby do you have an idea of how to make loop or something else to achive this taks?

there are more similar posts here.

use the search box.

Can you share link, I had problem to find it out?

Not trying to be rude, but some version of this question seems to come up at least once a week. Search for similar posts and you should find an answer explaining what’s going on and how to work around it. If you have any specific questions after that then let us know and we can try to answer them for you.

Forgive me, I have to improve my search skills, it’s my ~firs week on this forum when I’m active. And also I don’t know how to remove this topic in this situation.

No worries. If you found another post that solved your issue you can just link it here and mark that as the solution. No need to delete the topic if you’re still looking.

I really don’t know what to write in search console, is it problem with If function or generally with sublist?

Hi @Laura420, you can try searching for keywords like Nested Lists, Lacing control, If function, condition, etc.

Some of the topics may even have textual scripting as part of the solution as well. So could be helpful for you to try DesignScript or Python as well.

Searching for “if” is not going to return you many reliable results unless it’s in a specific phrase. You have to search for something like “if node”, “if function”, etc. The quotes are needed in this case to search the full phrase.

Here are a few examples:

hi guys,

Just a bit of my two cent’s worth. I think it might be the first list being the issue here. You have to resolve the null values that are appearing so… Designscipt-wise, you can type this in to get the values to be either true or false.


Then push that through your if formula.

If I got it wrong, then hope these would help you as much as it has helped me out when I first started my journey in Dynamo.


Good point. You certainly need to have a full list of true/false values before you can do anything with the If node.