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Ask HN: Teach me something new

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Re: Ask HN: Teach me something new

#721

Post by LargoLasskhyfv »

aasasd wrote: post #686
SemanticStrengh wrote: post #61

Earlier quoted context omitted.

I always found it strange how UFOs concentrate in the U.S,is it because of the climate? /s I wanted to believe and there is a serious subreddit for UFOs but most are debunked. There exist ~2 truly mysterious UFOs and most of their mystery has been explained.

> UFOs concentrate in the U.S. Obviously it's because when the aliens want to talk to the authorities, they go to the Supreme Democratic Leader of Earth.

...!YÄSS-SS-Ss-ss

(·) https://www.imdb.com/title/tt0080836/mediaviewer/rm391993728...

Re: Ask HN: Teach me something new

#722

Post by laserlight »

mdp2021 wrote: post #710
edgartaor wrote: post #568

Earlier quoted context omitted.

Magenta have not a electromagnetic frecuency. https://www.youtube.com/watch?v=8FSpCAs5KZg

It is the sum of two ranges (magenta is the sum of red and blue lights): it also exists "outside", like the rest. For that matter, not even "pinkish grey" is defined by simply a frequency (the hue is, the colour is not): the definition for this purpose was meant to be concise, not literal.

Your previous comment had stated that hues are electromagnetic frequency and parent comment showed a counterexample. Color is a complex phenomenon that cannot be reduced to electromagnetic frequencies and their composition. For an example, see impossible colors [0].

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

Re: Ask HN: Teach me something new

#723

Post by sideshowb »

beanlog wrote: post #692
sideshowb wrote: post #398

Earlier quoted context omitted.

Pianist here. I see where you're coming from, but I definitely do also rely on the different shapes of keys to know where I am without looking. I've been learning to play the button end of an accordion and personally I find the uniformity makes it harder. But maybe that's just what I'm used to. As an aside, I find c major a horrible key to play in, again I think the uniformity makes it harder and less ergonomic, but…

This is pretty eye opening to me, I would have never thought anyone found C major more difficult to play in than other keys. To me, difficulty is directly proportional to the amount of stuff in the key signature, but that may be because I've never had proper education (~5 years of lessons as a child from a very casual teacher).

The way we happen to notate music doesn't help to endear people to f sharp major, certainly! If you keep practising all the scales and try to learn to do more by ear/improvise, I'm pretty sure you'll end up enjoying other keys more.

Re: Ask HN: Teach me something new

#724

Post by joveian »

thunderbong wrote: post #529
aspaviento wrote: post #209

Harmonicas are amazing instruments. At first people assume them to be like toys (you can buy really cheap ones everywhere) and initially the concept seems really easy: 10 holes, drawing air produces some notes and blowing air produces other notes. But the more you get into it, the more amazing it gets. Soon you discover that you can bend notes by positioning your tongue in a specific way and your repertoire increases…

After reading your comment and its replies, I went looking on Youtube for some harmonica videos. I don't play the harmonica, and I don't have any idea about music. However, I do like the harmonica as an instrument whenever I hear it in some songs. I find that usually the harmonica always plays multiple notes together, and to my untrained ears, this always makes me feel that it can never hold the stage like maybe, a s…

Nice one, the only one of these posted harmonica songs I like, although I liked the melodica too. I've enjoyed the harmonica melodies in Falcom games (Ys Origin and Trails in the Sky are the two I can think of but I think there are others):

https://www.youtube.com/watch?v=mIROXLCXiQw

https://www.youtube.com/watch?v=4MGEqk6P3AM

There is also the similar size ocarina:

https://www.youtube.com/watch?v=1DHecFcDhbw

Re: Ask HN: Teach me something new

#725

Post by mdp2021 »

laserlight wrote: post #722
mdp2021 wrote: post #710

Earlier quoted context omitted.

It is the sum of two ranges (magenta is the sum of red and blue lights): it also exists "outside", like the rest. For that matter, not even "pinkish grey" is defined by simply a frequency (the hue is, the colour is not): the definition for this purpose was meant to be concise, not literal.

Your previous comment had stated that hues are electromagnetic frequency and parent comment showed a counterexample. Color is a complex phenomenon that cannot be reduced to electromagnetic frequencies and their composition. For an example, see impossible colors [0]. [0] https://en.wikipedia.org/wiki/Impossible_color

> Your previous comment had stated that hues are electromagnetic frequency and parent comment showed a counterexample

That was not the point, and said counterexample is not such (also magenta is, in a way, "electromagnetic frequenc[ies]"). Impossible colours - virtual colours - do go more towards the counterexample, though up to a certain point as they refer to the mental phenomenon of colour and leave the physical nature of colour untouched.

But finally I get what you meant when you stated: «not all colors are electromagnetic frequencies». True ("not all perception is produced by a direct influx of"). But also false, apparently (to the best of my), as objectivized hybrid colours are compositions of electromagnetic ranges; objectivized virtual colours are as well etc.

> Color is a complex phenomenon that cannot be reduced to electromagnetic frequencies and their composition

Yes, and nobody ever stated the opposite - no reduction was never implied, no «overlapping» (as written in the other post): the point was expressed, nearby, at https://news.ycombinator.com/item?id=31217999

Re: Ask HN: Teach me something new

#726

Post by mikelevins »

joveian wrote: post #716
mikelevins wrote: post #48

Earlier quoted context omitted.

One of the other weird things I referred to is best described as discovering that I could be awake and asleep at the same time. I think it might be another case of our naive ideas about cognitive processes being a little oversimplified. It sounds like nonsense, of course, but that's because we naively assume that sleep and wakefulness are opposites--that they are mutually exclusive. What if we're wrong about that? Wh…

I have several serious sleep issues including insomnia (not usually due to racing thoughts, just inability to sleep) and circadian issues. What you are describing sounds like what I call "half sleeping", although I can always move if I try (I'll also usually unintentionally wake myself up rather quickly when lucid dreaming and can then move almost immediately; I definitely do not have sleep paralysis, although possib…

This all sounds pretty much consistent with my guesses about what was happening. In particular, I'm predisposed to agree with your idea that sleep is a bunch of different processes that are normally well-coordinated. I hypothesize that the combination of my Chronic Fatigue Syndrome and the doses of modafinil disrupted that coordination, resulting in my experience of being awake and asleep at the same time.

Of course, just because we both came up with similar hypotheses doesn't mean we're right, but I'll take it as a tentative working theory for now.

Re: Ask HN: Teach me something new

#727

Post by mikelevins »

LargoLasskhyfv wrote: post #712
mikelevins wrote: post #28

I've described this on HN before; forgive me if you've already seen it. I have chronic migraine. It sounds worse than it is; I rarely suffer attacks anymore, and when I do, they're usually mostly harmless, as in the case I'll describe below. Contrary to popular belief, migraine is not a headache. It's something a little more like an epileptic seizure. Intense headaches are one common symptom, but there are a lot of o…

Hrm. I had similar experiences beginning a few weeks after a 'mild' TIA in the lower right part of my cerebellum in 2002. But it manifests itself slightly different. My whole field of view, both eyes disintegrates into something of a mix like a https://en.wikipedia.org/wiki/15_puzzle or one side of an unsolved https://en.wikipedia.org/wiki/Rubik%27s_Cube , 'scrambled' into about 250 to 400 fields. Not quadratic, and…

That's all super interesting; thanks for the description!

It's probably totally unrelated to any of this, but I also think primarily (though not entirely) nonverbally, and expressing myself always involves translating nonverbal thoughts into words.

And, for what it's worth, I'm a native English speaker trained (but horribly out of practice) in German (and Latin and Mandarin and Tibetan and Hungarian and Greek and Esperanto and Lojban --don't ask me to communicate in any of them without several weeks of remedial practice!).

Re: Ask HN: Teach me something new

#728

Post by mensetmanusman »

mikelevins wrote: post #28

I've described this on HN before; forgive me if you've already seen it. I have chronic migraine. It sounds worse than it is; I rarely suffer attacks anymore, and when I do, they're usually mostly harmless, as in the case I'll describe below. Contrary to popular belief, migraine is not a headache. It's something a little more like an epileptic seizure. Intense headaches are one common symptom, but there are a lot of o…

I’m sorry that you experience migraines, I have only experienced one in my life during a stressful stint in graduate school.

I lost, temporarily, the connection between what I wanted to say and the words that would come out. It was crazy.

Re: Ask HN: Teach me something new

#729

Post by senjin »

schoen wrote: post #619
senjin wrote: post #515

Earlier quoted context omitted.

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!

There is also "!!" for the entire prior command line. Someone elsewhere in this thread mentioned the usefulness of sudo !! for "run the entire previous command under sudo". Another example could be echo "!!" > myscript for "save the previous command into the file myscript".

I also use cat `which !!` every once in a while

Re: Ask HN: Teach me something new

#730

Post by senjin »

aasasd wrote: post #678
senjin wrote: post #515

Earlier quoted context omitted.

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.

I use zsh so this is also going in my toolbox. I think I've reached for !:* in the past and didn't know it so this is useful
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