Workaround with If statement and empty list

[vanman]

Hi, Can anyone help me with a work around for this to take the element when true. Also when theres an element in the empty I want it to take that one when its false.

[Bjorn_Keulemans1]

The IF often fails when the 2 “answers” are of a different rank (ie a list and a value), it’s a lot more predictable when both items are lists or just 2 single items.

[MVE1112]

I believe you could also use the ‘Scope if’ node when working with empty lists

The normal if node does not handle empty lists inputs correctly, the scopeif node does.

[jacob.small]

Via Design Script:
indx = DSCore.List.IsEmpty(a) ? 0 : 1 ;
rslt = [a,b][indx];

[vanman]

Thank you for the replies but still need a little more help please

This worked but not for going the other way around.

My dynamo dosn’t quite agree with the scope if node. I gave it a go before but it did odd things like corrupts the script then id have to copy the script to a new script for it to work again.

I’m probably not implementing the design script correctly…

[vanman]

This ended up working from your ideas

[jacob.small]

@vanman

Thank you for the replies but still need a little more help please

I put the [a,b] list backwards based on the previous indexing. My bad.

[Bjorn_Keulemans1]

Both inputs need to be a list in that implementation. you forgot the [ ] around the value.