Hello wizards, I am back for more of your awesome guidance. I am attempting to split lists of lists by true values. I have python script which works for a single list, but am lost when i have multiple lists how to get the python to work. Attached image shows the AllIndicesOf values for true values. I want to ultimately chop the lists at all these values to create new sublists. I think i need a loop or a zip function possibly but i have never used one. I am hoping i made sense and that someone can shed some insight to make this work.
Why Python? And does it have to be Python?
One liner to get indexes - assumes a list of lists with true/false
indexes = [[i for i, v in enumerate(lst) if v] for lst in IN[0]]
Now to slice the lists on the index
def slicer(values, indexes):
indexes.sort()
return filter(None, [values[s:e] for s, e in zip([0]+indexes, indexes+[len(values)])])
values = IN[1]
indexes = [[i for i, v in enumerate(lst) if v] for lst in IN[0]]
OUT = [slicer(v, i) for v, i in zip(values, indexes)]
It doesnât have to be python if you have a solution without it.
Good to know.
I allways like to provide non Python 
solutions (IF possible) for people who
donât know Python (like me 
)
Is @Mike.Buttery âexampleâ what you were after?
Python makes this really easy, but you can still do it with nodes. You just need to use the true indices to define start/stop sequences and be mindful of the list levels.
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Both @Mike.Buttery and @Nick_Boyts solutions work great. I guess it just depends on whether you like python or prefer use of nodes. Thank you much gentlemen!
I was experimenting and i came up with something like this 
.
But i would need some sort a CumulativeSum but one which would substract.
You can essentially do that really easily by just creating a list of âshifted indicesâ by adding 0 to the beginning and subtracting.
However, flattening the list means you no longer respect the original sublists. Not sure if thatâs whatâs intended or not.
2 Likes
Fair point. And thanks for the example how to subtract a value with the previous.
Learned something again today (thatâs i also why i post my brain farts sometimes 
).
If you have Python chops consider a yielding function, I use that for breaking down lists into chunks in this video and use this technique often when dealing with things like finding continuous periods of solar access.
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