Dictionaries with array-like interface

[dmm]

This low-key talk might have been the single most useful talk of the whole JuliaCon 2021:

Dictionaries.jl - for improved productivity and performance

pretalx.com/juliacon2021/talk/WRNAEN/

and live.juliacon.org/talk/WRNAEN (that is, www.youtube.com/watch?v=Y-hAZcqAw28)

github.com/andyferris/Dictionaries.jl

I am going to recall my recent brushes with advanced dictionaries (and with their reshaping into arrays) in the comments.

Comments

[dmm]

On one hand, there is my research draft of what one could do to accommodate nested dictionaries (structure with tree-like interfaces) inside machine learning frameworks optimized for hangling "tensors" (flat multidimensional arrays).

https://github.com/anhinga/2021-notes/tree/main/research-drafts

"Dataflow matrix machines, tree-shaped flexible tensors, neural architecture search, and PyTorch" (Jan 2021)

[dmm]

Then there is https://en.wikipedia.org/wiki/Hash_tree_(persistent_data_structure)

which is presumably behind all modern implementation of persistent data structures in Clojure and other languages:

https://lampwww.epfl.ch/papers/idealhashtrees.pdf (also posted here https://hashingit.com/elements/research-resources/2001-ideal-hash-trees.pdf )

These ideal hash trees are more like Tries ("Hash Array Mapped Trie").

Array Mapped Tries(AMT), first described in "Fast and Space Efficient Trie Searches", Bagwell [2000], form the underlying data structure.