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Re:The Periodic Table of Data Structures [pdf] by sytelus on Saturday October 27, 2018 @04:34AM (#18314878)
This is very inspirational but not sure if this is done in the best way. The core value of Mendeleev's approach is to find gaps and predict things that should exist but we haven't found yet. However for this to happen, one must isolate the "atoms" that can't be further broken down and identify the pattern in these atoms. The periodic table created in Figure 4 of this paper doesn't exactly sounds like isolation of "atoms" of data structures.
Re:The Periodic Table of Data Structures [pdf] by esturk on Saturday October 27, 2018 @06:53AM (#18315231)
You're right based on the modern day thinking of what the periodic table is but you're wrong to suggest that people knew what they were doing from the very start.

The formulation of the periodic table is quite like modern day data science. Chemists even before Mendeleev observed patterns and tried to build a model to predict missing ones. The beauty is that this was done without understanding the underlying mechanism of how it all worked, ie what makes an element (protons), what makes their periodicity (electrons). That came 50+ years later when we discovered protons and electron orbitals.

So going back to the article, their approach is fine because they're just formulating some model from observed patterns. Their reasoning for the underlying mechanism could be completely wrong but that's fine too until a better model comes along.

Re:The Periodic Table of Data Structures [pdf] by whatshisface on Saturday October 27, 2018 @08:07PM (#18318395)
>The formulation of the periodic table is quite like modern day data science.

That's because data science is just science. The only distinction is that you're studying somebody's sales pipeline instead of the secrets of the universe.

Re:The Periodic Table of Data Structures [pdf] by carapace on Saturday October 27, 2018 @12:07PM (#18316331)
FWIW I was able to kinda sorta do that for basic recursion combinators: http://joypy.osdn.io/notebooks/Recursion_Combinators.html#co...

In "Functional Programming with Bananas, Lenses, & Barbed Wire" http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.41.1... they talk about morphisms: Hylomorphism, Anamorphism, Catamorphism, Paramorphism.

If you break them down using Joy (programming language) in terms of the genrec general recursion combinator, they form simple patterns, which then suggest at least two other unnamed combinators:

Hylo-, Ana-, Cata-

    H == [P  ] [pop c ] [G          ] [dip F        ] genrec
    A == [P  ] [pop []] [G          ] [dip swap cons] genrec
    C == [not] [pop c ] [uncons swap] [dip F        ] genrec
Para-, ?-, ?-

    P == c  swap [P  ] [pop] [[F        ] dupdip G          ] primrec
    ? == [] swap [P  ] [pop] [[swap cons] dupdip G          ] primrec
    ? == c  swap [not] [pop] [[F        ] dupdip uncons swap] primrec

Etc.
Re:The Periodic Table of Data Structures [pdf] by Sirupsen on Saturday October 27, 2018 @07:14AM (#18315263)
I am fascinated with unifying theories such as the periodic table (Mendeleev's) and the Copernican view of planets orbiting the sun. The previous, Earth-centric model had more deviations than predictive power. The periodic table is also an example of a structure with tremendous predictive power.

I think it's also interesting to distinguish between systems that reveal intrinsic order (e.g. periodic table), and systems that superimpose external order (e.g. a performance review framework).

Behavioural economics is an example of a field that desperately needs a modern-day equivalent of Mendeleev to come around and structure.

I am craving more examples of this, please, anyone, share!

Re:The Periodic Table of Data Structures [pdf] by r-bryan on Saturday October 27, 2018 @10:42AM (#18315867)
I can't find it now but I recently read of one or two guys who systematically tabulated juggling tricks. Gaps in the table led to new tricks which astonished experienced jugglers -- the way gaps in the periodic table led Mendeleev to predict properties of undiscovered elements. One guy gives talks on juggling at math conferences and on math at juggling conferences.
Re:The Periodic Table of Data Structures [pdf] by gwilliams on Saturday October 27, 2018 @10:24PM (#18318809)
This reminds me of the effort to enumerate all ways of tying a necktie: http://www.tcm.phy.cam.ac.uk/~tmf20/tieknots.shtml
Re:The Periodic Table of Data Structures [pdf] by theoh on Sunday October 28, 2018 @08:34AM (#18320337)
Re:The Periodic Table of Data Structures [pdf] by severine on Sunday October 28, 2018 @12:22PM (#18321319)
Re:The Periodic Table of Data Structures [pdf] by TuringTest on Saturday October 27, 2018 @10:09AM (#18315746)
If you know programming, you may enjoy Peter Van Roy's components of programming paradigms.

https://en.wikipedia.org/wiki/Programming_paradigm#Overview

Re:The Periodic Table of Data Structures [pdf] by frutiger on Saturday October 27, 2018 @07:32AM (#18315296)
Physics is full of such examples.

Newton’s theory of gravitation unified the motion of apples falling from a tree, cannonballs thrown into walls, the motion of planet earth around the sun, and even motion of all the known planetary bodies.

Electromagnetic waves gives us one understanding of X-rays, gamma radiation, visible light, infrared, radio waves, etc.

Quantum field theory unifies every microscopic theory of matter and energy we have ever known.

This list could be much longer.

Re:The Periodic Table of Data Structures [pdf] by kopo on Saturday October 27, 2018 @07:27AM (#18315287)
They removed the image from the main article for some reason but I thought this was cool - https://en.wikipedia.org/wiki/File:The_Cognitive_Bias_Codex_...
Re:The Periodic Table of Data Structures [pdf] by espeed on Saturday October 27, 2018 @05:47PM (#18317871)
Here's an eclectic mix of examples from various perspectives across multiple domains. Understanding the representation of knowledge and the fundamental structure that underpins the connective essence of things is one of the prime ideas that drives my thinking, and as a consequence much of what I post about on here is related to that in some way. Below is a brief sampling of examples related to this idea, and for a more extensive list, browse through my postings (and if you can see how they all connect, let me know!).

In general, see the Classification of Finite Simple Groups [0]. In terms of specific examples, the minimal classifications of knots [1], trees [2], and braids [3] are 3 instances that popped to mind. From a number-theoretic perspective, the paper Enumerating the Rationals and its derivative works are interesting reads. In terms of spatial structure and spatial decomposition, look at the classification of crystal structures [4], lattices, polytopes (zonotopes are particularly interesting), periodic and aperiodic tilings, the classification of space-filling curves, and the classification of closed surfaces [5]. From a relational perspective, look at the classification of topological spatial relations [6] and Allen's interval algebra [7]. And the one my intuition finds most intriguing is the classification of Group Theory Single Axioms and its relation to my conjecture that division is primary.

[0] Classification of Finite Simple Groups https://en.wikipedia.org/wiki/Classification_of_finite_simpl...

[1] Prime Knots https://en.wikipedia.org/wiki/List_of_prime_knots

[2] Enumerating Trees https://www.cs.virginia.edu/~lat7h/blog/posts/434.html

[3] Braid Group https://en.wikipedia.org/wiki/Braid_group

[4] Crystal Structure https://en.wikipedia.org/wiki/Crystal_structure

[5] Classification of Closed Surfaces https://en.wikipedia.org/wiki/Surface_(topology)#Classificat...

[6] Topological Spatial Relations https://en.wikipedia.org/wiki/Spatial_relation

[7] Allen's Interval Algebra https://en.wikipedia.org/wiki/Allen%27s_interval_algebra

[8] "Yet Another Paper on Group Theory Single Axioms" https://www.cs.unm.edu/~mccune/projects/gtsax/

P.S. Clifford Algebra / Geometric Algebra [00] unifies much of mathematics, e.g. in GA, Maxwell's equations can be reduced to one equation and expressed on one line [01]:

[00] Geometric Algebra https://en.wikipedia.org/wiki/Geometric_algebra

[01] Maxwell's equations formulated in terms of Geometric Algebra https://en.wikipedia.org/wiki/Mathematical_descriptions_of_t...

Re:The Periodic Table of Data Structures [pdf] by kevmo on Saturday October 27, 2018 @05:30PM (#18317766)
The Structure of Scientific Revolutions by Thomas Kuhn discusses paradigm shifts and periodic re-unifications of theory and fact.
Re:The Periodic Table of Data Structures [pdf] by 7373737373 on Sunday October 28, 2018 @09:29AM (#18320498)
Does anyone know one of these for financial contracts?
Re:The Periodic Table of Data Structures [pdf] by chriswarbo on Sunday October 28, 2018 @10:40AM (#18320769)
Re:The Periodic Table of Data Structures [pdf] by 7373737373 on Friday November 02, 2018 @02:11AM (#18361011)
I love that paper.
Re:The Periodic Table of Data Structures [pdf] by fsavard on Saturday October 27, 2018 @08:44AM (#18315482)
I confess I haven't read the whole thing but that figure 4 looks more like a set of approaches, rather than a continuum as in the periodic table.

Their figure 1, which appears to describe fundamental design tradeoffs, makes me think of CAP theorem "maps", like this:

https://www.researchgate.net/figure/CAP-Theorem_fig4_2214620...

But the whole idea of figuring out first principles and "fundamental" design choices is quite appealing. They have a section saying that a big goal here would be automatic design of optimal data structures. They talk of machine learning techniques (they mention Bayesian optimization and reinforcement learning).

That seems a very interesting research direction. In the same vein there's this talk by Jeff Dean about how they use ML at Google to replace all sorts of heuristics in data structure design (bloom filters etc.) with machine learning to optimize performance, though from what I recall it doesn't automatically change the algorithm itself:

http://learningsys.org/nips17/assets/slides/dean-nips17.pdf

(discussed on HN previously https://news.ycombinator.com/item?id=15892956)

EDIT: I think they cite a paper by Dean and others which was part of that talk

Re:The Periodic Table of Data Structures [pdf] by eternalban on Saturday October 27, 2018 @09:29AM (#18315601)
> I confess I haven't read the whole thing

This is a sort of functional bug in forums such HN.

Commenting on paper like this requires time to digest and reflect on the content. For a conceptual paper such as OP I would need at least a day (to figuratively sleep on it) but returning a couple of days later to make (hopefully) informed comment is no longer interactive. There is archival and future reference value, of course, but then rebuttals to possible misconceptions will not accompany the comment.

Re:The Periodic Table of Data Structures [pdf] by fsavard on Saturday October 27, 2018 @09:49AM (#18315674)
It's quite funny I made a very similar lament a while ago:

https://news.ycombinator.com/item?id=16230668

I only post when I think I can somehow add value to the discussion, at least value for some people who might read the comment. Obviously some people with in-depth knowledge of the paper and field in general will probably already be aware of the link I posted (for example), but others might find it an interesting avenue to explore. I know I often come to HN comments for this reason: a topic seems interesting, I want to learn of related stuff and/or get opinions from people with deeper expertise.

So even if it's only for "future reference", it might actually bring value _for some_. At least that's what I tell myself :)

Re:The Periodic Table of Data Structures [pdf] by detaro on Saturday October 27, 2018 @01:36PM (#18316781)
Yeah, that and tracking long-running topics are things old-fashioned forums (phpBB style) are better at than the newer, more ranking-oriented ones (HN, reddit, ...), since old discussions can be pushed up again.
Re:The Periodic Table of Data Structures [pdf] by mkesper on Sunday October 28, 2018 @10:32AM (#18320730)
Although long forum threads only really work if someone regularly updates the first entry with newest infos.