Dearest Pd crowd,
it is finaly time for me to learn some data structures! I need a structure where i have a nested array:
(array1 (array2(float)))
array1 should have 200 slots of
array2, needs 10 slots of
float
the setup seems to work, but somehow i can not set, or get a number out of my structure.
May someone enlighten me? I hope you can follow with this:
nestedArrays.pd

EDIT: setting the number like in the patch seeams to work. I can see it right clicking the properties of the structure in the data window. But retrieving it is not working. Am i doing something wrong with the pointer??

Hi,

[traverse window, bang( is to append data, the pointer points to the created item.

If you want to retreive data, it's [traverse window( and then how many [next(s needed for the pointer to point towards the target item.

or you store the pointers in a list to access them: https://forum.pdpatchrepo.info/topic/11435/access-pointer-with-list-store

@kyro i think it works now like you sugested (still not too sure with pointers). I "needed" to use append, even though i dont want to append anything, console gives me an error, but still the pointer is correct. And after setup, i can use the [traverse window, next( to retrieve the data.
@jona the list-store is interesting and would have been usefull if i had not nested the arrays i think.

@Johnny-Mauser This is all somewhat interesting, but maybe a bit overkill and can probably easily be solved with [text]:

text-store.pd

To access a value within a data structure, you need a pointer. To get this pointer after the value has been stored, you would probably have to store all the pointers within a list as @Jona pointed out. To get the right pointer, you would then have to build some kind of directory to map the coordinates of array1 and array2 to the index of the list where the pointer is stored. This directory would probably been build with [text].

So instead of storing the index of the list that contains the pointer to the value, you can simply store the value directly, as shown above

Yes, it is possible to access the data structures with [until] and [next( if you also store an index for each data structure, but [text search] does this in a far more elegant way

@ingox thanks for this insight in [text]. @Jona allready showed some way for the original task in this thread. Your examples of write and read look quite simple indeed; probably this would have been easier than my atempt with DataStructures. Anyway i have a hope to visualize it with the DataStructures as well. Maybe this would also have been easier with [text] because it seems i have to retrieve all the data from the arrays anyway before being able show it.

@Johnny-Mauser Yes, what i did is the storage part. You could build the logic and the visualization separately, which should also be more straight forward using [text] instead of data structures. I don't think nested data structures would help with the visualization

Well, to use the graphical aspects of data structures you don't need to retrieve the data. By writing a value into the structure it will be rendered, if there are drawing instructions present. Still, i believe also for that a simpler data structure would help

Last time I checked there was a bug with the hotspot of children nested datastructures:
https://sourceforge.net/p/pure-data/bugs/358/