List index?

Replies to This Discussion

Permalink Reply by Danny Boyes on September 1, 2011 at 8:25am

Your list of values are not held in the same memory as the list you are searching. Therefore they are not the same items. You can only find the index of an item if it is in the list. i.e. has come from the list and you are checking where it came from.

 

Another way of thinking about it is to have a room full of people and you need to find one person but instead of being able to simply say their name you need to provide a DNA sample before they own up, and the only way to get a DNA sample is to take blood from this person.

Permalink Reply by RG on September 1, 2011 at 9:19am

so...list index doesn't work!

Thanks for the DNA:)

 

Permalink Reply by Danny Boyes on September 1, 2011 at 9:38am

Not how you imagine it would, it is not a search feature.

Permalink Reply by Michael Pryor on September 1, 2011 at 9:21am

thats a mindf****, You can only identify him with his DNA, but you can only get his DNA from him personally, in which case you would already know him.

Permalink Reply by RG on September 1, 2011 at 9:34am

I really dont understand why they do it with "DNA", make no sense...

 

Permalink Reply by RG on September 1, 2011 at 9:35am

Can't be grasshopper more efficient?

 

Permalink Reply by Danny Boyes on September 1, 2011 at 9:36am

The fact that you know him is the reason you want his index.

 

It comes in handy for instance if you Create Set where you are removing identical items from a list to create a unique set of values. The question is which values did you use from the original list, up steps List Index

Notice that I didn't use the K output because that is not the same as the actual list that you are sorting in A

 

PS: I believe that David is going to add the output i to the Create Set Component anyway, but it doesn't mean that List Index is redundant. 

Permalink Reply by Brian Harms on December 1, 2011 at 8:32pm

It looks like you can use it as a totally decent search feature:

Although as it's been pointed out, member index does this more cleanly.

Permalink Reply by Brian Ringley on February 18, 2013 at 12:18pm

@Michael haha

@Danny and @Brian thank you for the clear explanation on Member Indices - this particular List component's behavior had been confusing me as I try to sort daylighting data out of Ladybug.

I think I was trying to force it to do what the Find Similar component does. Anyway, got it working now.

Permalink Reply by Ram Joshi on October 17, 2016 at 3:59am

Hi Briam,

Thanks for this workflow. It stands useful even after half a decade!!

Cheers!!