Let’s say I have a list [2, 6, 1, 9]. Is it possible to get the position of the number in the list? For example if 6 is the input, the output would be 2 because it"s the second number in the list.

You can make a parallel list and use a conditional statement. The graph Desmos | Graphing Calculator shows an example of how to get the first occurence of a 6 in a list, though it doesn’t quite know what to do if no 6 shows up.

That’s exactly what I needed and I was able to replicate it for my needs. Thank you!

I can’t quite get my head around how that works. Could you explain what is happening?

Don’t worry. I’ve got it.

You can make fewer expressions by nesting list N and editing position to this:

p_{osition}=min({L=6:[1…length(L)],length(L)+1})

Can you make a version of this that works for points?

It’s a little ugly, but I think this works:

This is essentially the same as Dan’s with an alternate approach, but here are two functions: one that returns the first index and one that returns all the indices. Depending on your needs, you could also adjust the tolerance needed to match points.

Oh, using distance is smart, I didn’t think of that at all. Now I also see how you are using a list of indices and limiting that list to conditions that are met, instead of creating a list of valid indices and then finding the smallest. That’s a new technique for me that really simplifies things… I’ll have to remember that!