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mrkgnao

1,913 karma · joined March 29, 2016

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mrkgnao··on Brief aerobic exercise immediately enhances attention and perceptual speed
> you become dizzy with too much O2 in your blood

I've never heard of this, can you elaborate?

mrkgnao··on Skip – A programming language to skip the things you have already computed
Can anyone comment on the similarities with (apparently somewhat less sophisticated) laziness as in Haskell, or the memoisation/caching done by the Nix package manager, or (perhaps most interestingly) the approach of the Funflow library for Haskell[1]?

[1]: https://www.tweag.io/posts/2018-07-10-funflow-make.html

mrkgnao··on Show HN: Memex – annotate and instantly recall any website
This looks interesting. I'm open to replacing my current (actually quite rudimentary) "capture to org-mode" setup. Is there any way to dump all/important parts of the information Memex captures to plain text/CSV/etc, or, say, a sqlite database?

Overall, this is a space I'm very interested in and this looks like a polished product. I'll be keeping an eye on it; I've installed the addon and am looking forward to playing with it :)

PS. "Full-text search" seemed to me (and might to many) like full-text search of webpage contents, not just URLs/titles. It's not malicious, of course, but it feels slightly misleading.

mrkgnao··on Ask HN: How can one be educated, smart, and believe in God?
I find it profoundly unsatisfying, but this may be a good starting point for further exploration:

https://en.wikipedia.org/wiki/Non-overlapping_magisteria

mrkgnao··on How to Name a Baby (2013)
It is a thing, and there's evidence for it in certain academic fields. [0] studies this effect in economics, and this would be reason to expect similar things in other fields like maths, CS, and physics where alphabetical surname order on research papers is standard. Modulo a lot of context, replicability issues, and the like (and of course career choices), there's a chance you actually are doing your daughter a tangible favour this way. :)

> Faculty with earlier surname initials are significantly more likely to receive tenure at top ten economics departments, are significantly more likely to become fellows of the Econometric Society, and, to a lesser extent, are more likely to receive the Clark Medal and the Nobel Prize.

> These statistically significant differences remain the same even after we control for country of origin, ethnicity, religion or departmental fixed effects. As a test, we replicate our analysis for faculty in the top 35 U.S. psychology departments, for which coauthorships are not normatively ordered alphabetically. We find no relationship between alphabetical placement and tenure status in psychology.

[0]: https://www.aeaweb.org/articles?id=10.1257/08953300677652608..., "What's in a Surname? The Effects of Surname Initials on Academic Success"

mrkgnao··on Agent Maps – OS Library for Simulations Atop Maps
Flagged. This breaks the Show HN rules: OP is not the creator of this.

I know the author; they shared it privately with friends and weren't ready to post this publicly yet.

mrkgnao··on ‘Why didn’t you think this baby was ill?’ Decision-making in acute paediatrics
This was posted elsewhere on this page:

http://www.seilevel.com/requirements/visual-models-save-live...

mrkgnao··on S2 Geometry
Quick note that may be of interest: S² is the mathematical notation for the "2-sphere", aka what we call a sphere in everyday language. I suppose that's explained by this:

> A unique feature of the S2 library is that unlike traditional geographic information systems, which represent data as flat two-dimensional projections (similar to an atlas), the S2 library represents all data on a three-dimensional sphere (similar to a globe).

(S^2 if the superscript character doesn't show up for you.)

mrkgnao··on ‘Why didn’t you think this baby was ill?’ Decision-making in acute paediatrics
> Physiological values are complex in paediatrics. They are more than complicated because although there are published ‘normal values’ which will guide the clinician in knowing whether a child is tachycardic or tachypnoeic, these are in fact reference ranges that were initially based on expert opinion. Although meta-analysis shows these reference ranges to be at least somewhat valid, it is probably safest not to think of them as ‘normal ranges’ at all since much of the data includes children in abnormal circumstances. Indeed, the clinician who relies on these values will by definition be unlikely to have a ‘normal’ child in front of them.

Relatedly, I'd imagine that (akin to the story about choosing what parts of a fighter plane to armour) the worst health emergencies, esp. in children, are the ones where the child does not make it to the ER alive or is either unresuscitable (word?) or deteriorates rapidly and uncontrollably before a diagnosis can be made.

mrkgnao··on Setting up a second keyboard for more shortcuts in Emacs
I mean, if a piano (or something closer to a Tonnetz[0] layout) is okay, why not a full organ with >1 keyboard and pedals? :)

[0]: https://en.wikipedia.org/wiki/Tonnetz

mrkgnao··on AMD Threadripper 2990WX 32-Core and 2950X 16-Core Review
> Because the two NUMA nodes are ~entirely independent, it's capable of running two independent processes at full speed.

I don't understand. From my (admittedly little better than layperson's) knowledge, I'm guessing the cores of most multicore processors have to compete for memory access...? Is there a good search term I can use to help me understand what's going on here?

mrkgnao··on A Poet of Computation Who Uncovers Distant Truths
Cavafy's The Satrapy, mentioned in the article (and a poem I love very much myself):

http://www.cavafy.com/poems/content.asp?id=60

mrkgnao··on I’m a very slow thinker (2016)
Alexander Grothendieck, one of the most influential mathematicians of the 20th century, on cognitive "facility" and giftedness:

   Since then I’ve had the chance in the world of mathematics that bid me welcome,
   to meet quite a number of people, both among my “elders” and among young people
   in my general age group who were more brilliant, much more ‘gifted’ than I was.
   I admired the facility with which they picked up, as if at play, new ideas,
   juggling them as if familiar with them from the cradle–while for myself I felt
   clumsy, even oafish, wandering painfully up an arduous track, like a dumb ox
   faced with an amorphous mountain of things I had to learn (so I was assured)
   things I felt incapable of understanding the essentials or following through to
   the end. Indeed, there was little about me that identified the kind of bright
   student who wins at prestigious competitions or assimilates almost by sleight
   of hand, the most forbidding subjects.

   In fact, most of these comrades who I gauged to be more brilliant than I have
   gone on to become distinguished mathematicians. Still from the perspective or
   thirty or thirty five years, I can state that their imprint upon the
   mathematics of our time has not been very profound. They’ve done all things,
   often beautiful things in a context that was already set out before them, which
   they had no inclination to disturb. Without being aware of it, they’ve remained
   prisoners of those invisible and despotic circles which delimit the universe of
   a certain milieu in a given era. To have broken these bounds they would have to
   rediscover in themselves that capability which was their birthright, as it was
   mine: The capacity to be alone.
(from Récoltes et Semailles)
mrkgnao··on Dads Pass on More Than Genetics in Their Sperm
Most sperm, too, are beaten to it by others
mrkgnao··on Elon Musk offers to help Thai cave rescue
Partly PR (like everything he does) and such unflattering things, but also partly an exercise of the ability (read "ubiquitous nerd dream" if you like) of thinking up outrageous solutions to pressing problems (e.g. inflatable "bouncy castle" air tunnel), which in this case differs from the usual in that said nerd is very rich (and also owns technology and employs people with skills appropriate to the problem) so the outrageous solution has some chance of actually being implemented in the real world

This differs from the option mentioned by someone else of "calling the right people" (perhaps by donating a chunk of money to send conventional rescue personnel/equipment) instead of flashily taking matters into his own hands: this is a display of ingenuity/out-of-the-box thinking/"a tunnel-making company that everyone says is a bad idea saved actual lives, see?" first (again, read something like "nerd saviourism" or a restricted form of "tech solutionism" if you like) and philanthropy second.

Similar idea to pushing his batteries in Puerto Rico, and also explains his lack of interest in Flint (often mentioned on Twitter) or similar humanitarian concerns, and hence his difference from a certain "philanthropic billionaire" stereotype exemplified by Gates and Buffett: he doesn't own a company that claims it can purify water in a way everyone thinks is either overpriced or stupid, so "those things would prove nothing". (A silly prediction along these lines: if there ever is some sort of emergency in the near future that requires transporting something very quickly from A to B, faster than a cargo airplane (and insert other wildly improbable things here), I'd expect him to offer to do the "NYC to Tokyo in 30 min" thing for free.)

mrkgnao··on It was raining in the data center
> like a thunderstorm formed from two opposing weather fronts, the physicality of outside Prineville air met the everywhere-ness of inside space in an impossible, non-Euclidean intersection

Not every word is a pretty one you can throw around, you know: what exactly about this metaphorical meeting was "non-Euclidean"?

mrkgnao··on Comparing the C FFI overhead in various programming languages
Haskell has one of my favourite C FFIs, and there are also libraries that let you seamlessly mix C into Haskell expressions:

http://hackage.haskell.org/package/inline-c-0.6.1.0#readme

mrkgnao··on Show HN: Telescope – News and RSS Reader
Erm, the link in 3. leads to http://zoziapps.ch/web-subscriber/ -- which just seems like a bunch of body text with no links in it.
mrkgnao··on How Cambridge Analytica’s Facebook targeting model really worked
Alternatively, "If I take a FLAC you own, make a 320kbps MP3 from it, and store it on my laptop, am I still in possession of any IP belonging to you?"
mrkgnao··on Introducing TensorFlow.js: Machine Learning in JavaScript
A good set of Haskell bindings to the TensorFlow library:

https://github.com/tensorflow/haskell

mrkgnao··on Some Notes About How I Write Haskell
This is a nifty thing made possible by the MonadFail class, which defines how a monad treats or recovers from a failed pattern-match.

    When a value is bound in do-notation, the pattern on the
    left hand side of <- might not match. In this case, this 
    class provides a function to recover.
https://hackage.haskell.org/package/base-4.10.1.0/docs/Contr...
mrkgnao··on How it works: Compiler Explorer
Fun fact: the Vim plugin for my browser gave me the link hint "SSE" for the "<n> comments" link on the front page.
mrkgnao··on Reasoning About Program Behavior Algebraically [pdf]
From experience (the last time slides for a talk by Stephen Diehl made its way to the HN frontpage), there's a lot of information in the actual (recorded) talk that the slides are going to be missing.
mrkgnao··on Opinions on functional programming and OCaml
If you do raise that then it's no longer an argument against partial application or "high[er] order functions", since you can't really call `fn` partially applied if fn and x => fn(x) aren't equivalent.
mrkgnao··on Opinions on functional programming and OCaml
How does record access work? Is it via generated record accessor functions (pretty crappy, used by Haskell) or does OCaml now have true row types (as in PureScript (and perhaps Elm))? Can you have multiple types with the same record field name?
mrkgnao··on Opinions on functional programming and OCaml
I agree with you on namespacing: I've found myself having to add prefixes myself when working with a bunch of similar datatypes with identically-named constructors (e.g. terms and types in a compiler have many similarities).

Saying "non-argument" and ending it there is not useful, but in this case it's shorthand for something along the lines of "not even wrong", and I think that's a valid answer for some (not all!) of the points in the OP.

To pick one example: the author gives an example of an eta-reduced function and then says:

    let fn1 a b c d = ... do something ...
    let fn2 a b c = fn1 a b c
    fn2 a b c d
> and you're like ...wtf... where the hell does d come from.

(Or their criticism of partially-applied functions, which is essentially the same thing.)

This is a "non-argument": the only thing that is being made clear here is that the author hasn't spent sufficient time learning the idioms of an unfamiliar style of programming. Yes, horrible partial-application like

    f = (g .) . ($) . (. (. h))
or whatever is always a bad idea, but saying that writing

    map f
is always worse than

    map (\x -> f x)
is much more likely to be a symptom of unfamiliarity than a deep, cutting critique of functional programming style.
mrkgnao··on Opinions on functional programming and OCaml
> This rebuttal isn't very good.

I'm inclined to agree, and I do find your points more "airtight".

(I see you've been downvoted; it wasn't me.)

mrkgnao··on Opinions on functional programming and OCaml
There's a point-by-point rebuttal in the comments that is also worth looking at:

https://gist.github.com/vjeux/cc2c4f83a6b60d69b79057b6ef651b...

In my own opinion, I think the author would be better served by sticking with it for a little while longer.

And, no, to head off one common strand of arguments at the pass: no, as a Haskeller and FP enthusiast, I (very strongly) do not think pure, statically-typed, globally-type-inferred (?) programming is perfect or some kind of One True Way. Does it have warts? Of course it does, and don't believe anyone who tries to tell you otherwise.

But the pure FP way of thinking has a lot to offer, and seeing all its idioms through an imperative, C-family-language lens is counterproductive.

A good thing to keep in mind here is the "Principle of Charity": when faced with an unfamiliar spin on something you know how to do in a different way, it's useful not to approach it with the intent of disproving it. Existential Comics has a guide[0] to learning philosophy as an amateur that talks about this.

[0]: http://existentialcomics.com/blog

mrkgnao··on Bernoulli Numbers and Ideal Classes (2008) [pdf]
I know, but it's good to understand the _trivial_ fractional ideals first. :)

(I like your blog, btw!)

mrkgnao··on Bernoulli Numbers and Ideal Classes (2008) [pdf]
Borderline surprised this is on the frontpage. :)

Here are two comments from yours truly on what "ideals" are and why they make sense to think about for number theory:

https://news.ycombinator.com/item?id=14016396

https://news.ycombinator.com/item?id=14017178

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