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Ask HN: Teach me something new

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Re: Ask HN: Teach me something new

#671

Post by Beldin »

morninglight wrote: post #588
rawoke083600 wrote: post #301

ok I'll have a go ! Here is my favorite mental-model for problem solving (and my favorite analogy) So I have this problem: I love eating scramble eggs, I hate cleaning up the pan and have been trying over the years many different techniques to make sure the egg's doesn't stick to the pan. (No I don't want teflon thanks). So I tried different oils, temperatures and techniques, all with the goal of getting those delici…

I had a girlfriend in Amsterdam who taught me to make scrambled eggs in a double boiler. This keeps the eggs at the temperature of boiling water. The result is so much better (light and fluffy) that you will never use your skillet again. I have heard that there are special large double boilers that are used to prepare scrambled eggs for restaurants, but I have never seen one. .

For anyone wondering what a "double boiler" is: it's cooking au bain marie.

Re: Ask HN: Teach me something new

#672

Post by SemanticStrengh »

andbberger wrote: post #668
SemanticStrengh wrote: post #652

Earlier quoted context omitted.

Come on, who do you think you are talking with? I have read many papers about C.elegans and my claims are backed up: "the inability to reliably identify all neurons within whole-brain recordings has precluded a full picture with circuit-level details." "we expect our work to aid in these endeavors (Bargmann and Marder, 2013; Brennan and Proekt, 2019; Kaplan et al., 2020; Kato et al., 2015). A richer set of network re…

i really couldn't care less how many papers you've read. whole brain calcium imaging is routine, no one expects it to be the whole picture. it's useful though. and no it is not a matter of debate, there are precisely 302 neurons

it's useful and yet understanding how brain works precisely require better instruments and datasets hence the understanding of the brain is not bottlenecked on infinite complexity but before anything, on good old metrology. Q.E.D

oh yeah well done completely avoiding the PNS question, so according to you neurons in the tail are relevant to worm cognition? spoiler except for tail local stimulus (e.g. tactile, heat) I doubt it

Re: Ask HN: Teach me something new

#673

Post by arnarbi »

_zywo wrote: post #247
arnarbi wrote: post #115

xp is a quick way in vi to swap two adjacent characters (a common typo correction) Ctrl-T does the same in emacs, and also in readline based programs like bash, as well as everywhere on macOS.

> xp I always thought the fact that Vim had automatic buffer copying and forced me to use "0p instead of p was really annoying. Looks like there is an actual reason for it after all :)

(Apologies if I’m misunderstanding and you already know this.)

Not specifying a register (e.g. "0) just means the commands, including x and p, will use the " register, aka the unnamed register. By itself, p is equivalent to ""p.

:reg shows you all the registers and their current contents.

This seems like a good description: https://www.brianstorti.com/vim-registers/

Edit: Oh I guess you are saying it was unexpected that delete or change commands clobber yanked contents of the unnamed register.

Re: Ask HN: Teach me something new

#676

Post by cheeselip420 »

amin wrote: post #2

Quantitative easing (sometimes mistaking called "money printing") isn't directly inflationary. Because when central banks buy bonds, they do not pay with normal money. Instead, they pay with a special type of money that can never enter the real economy (as to not create inflation). This special type of money are called "bank reserves". And bank reserves can only be used to 1) settle interbank transfers and 2) buy mor…

This is a dumb take. By using "reserves" to buy bonds, it means cash that WOULD have purchased those bonds (like a pension fund or your vanguard fund) is now going... somewhere else. Like stocks. If that money goes to stocks instead, then the price will rise. So while it may not be DIRECTLY inflationary, its only like 1 level removed.

Re: Ask HN: Teach me something new

#677

Post by mikelevins »

schoen wrote: post #622
mikelevins wrote: post #422

Earlier quoted context omitted.

I didn't mention it, but I really like them. I mean, they're inconvenient, and they make me nervous because for most of my life they were followed by the horrible parts of a migraine, but the scotomas themselves are just so beautiful and interesting that I like them anyway. And in recent years I've been able to enjoy them without so much of the horrible parts afterward.

Is the scotoma similar to the effects that you get by applying pressure to your eyeball? https://en.wikipedia.org/wiki/Phosphene#Mechanical_stimulati... Or is it quite different?

Pretty different. I used to like to induce pressure phosphenes. I found that a hazard of it was that more pressure produced more spectacular light shows, but that direction led to sore eyes.

Re: Ask HN: Teach me something new

#678

Post by aasasd »

senjin wrote: post #515
schoen wrote: post #139

Earlier quoted context omitted.

Wow, I did not know that! I would have referred to this using !$, which is one of the Bourne shell history substitutions. Like $ mkdir awesome $ cd !$ (The "!" has the connotation "history" in the shell, while the "$" has the connotation "last", as in regular expressions.) An advantage of the way you mentioned is that you could actually see the history item displayed on the command line before running the command!

I use !$ multiple times every day but you just helped me make the connection to try !^ for the first argument and I think I'm going to start using that as well. Thanks!

At least in zsh, there are also !:1 for the first argument, et cetera with the rest of natural numbers, and something like !:* for all the arguments without the command.

The generic form is !n:m for n-th last command line and m-th argument, with an omitted n being a shortcut for the last line.

Not sure if all of this works the same in bash.

Re: Ask HN: Teach me something new

#679

Post by operator-name »

jonah-archive wrote: post #89

The big bang was extremely hot; the universe now is quite cold (microwave background). It was a continuous process of cooling, implying that there was an interval where the entire universe was comfortable (there are at least a few papers on this, e.g. https://arxiv.org/abs/1312.0613 , but I like it more just as a strange thing to thing about).

There's also the slightly more complex hairy ball theorem, such that a combed hairy ball will always have 2 cowlicks (or that on earth there will always be two places with exactly the same temperature, or the exactly same wind speed).

Re: Ask HN: Teach me something new

#680

Post by schoen »

gnubison wrote: post #631
schoen wrote: post #139

Earlier quoted context omitted.

Wow, I did not know that! I would have referred to this using !$, which is one of the Bourne shell history substitutions. Like $ mkdir awesome $ cd !$ (The "!" has the connotation "history" in the shell, while the "$" has the connotation "last", as in regular expressions.) An advantage of the way you mentioned is that you could actually see the history item displayed on the command line before running the command!

History expansion originated in csh, and was never in the Bourne shell. Bash, certainly.

Thanks for the correction. I often recognize when bashisms are bashisms, but I didn't realize that was.
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