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Ask HN: Teach me something new

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Re: Ask HN: Teach me something new

#601

Post by sleightofmind »

mikelevins wrote: post #524
myownpetard wrote: post #298

Earlier quoted context omitted.

It is so annoying that standard guitar tuning isn't all perfect fourths and we've decided to throw in a major third between the G-B strings. Bar chords be damned, I want to be able to visualize it symmetrically and have chord shapes that work the same across the fretboard.

You might like the Linnstrument: https://www.rogerlinndesign.com/linnstrument As a longtime guitarist myself, I found it quite easy to learn. You can think of each row as a guitar string. In the default setup, each row is a perfect fourth above the row below. The green lights are the white keys on a piano; the unlighted keys are the black ones. The blue lights are C natural. Skip a square diagonally up and to the rig…

I watched the LinnStrumentalist video per your first link. Amazing stuff. And it does seem to reduce the amount of finger contortion required compared to most keyed or stringed instruments.

It does, though, seem to demand that the player look at the keyboard. For an instrumentalist, this may not be a big deal. For a performer accustomed to connecting to his audience with his face, as do many singers, it seems like a big drawback.

That said, color me amazed.

Re: Ask HN: Teach me something new

#602

Post by mncharity »

omnibrain wrote: post #240
mncharity wrote: post #6

Consider arm sized, hand sized, fingernail sized, and pinched-fingers "tiny" sized. About 1000, 100, 10, 1 mm. Tray of cookies, hand-sized cookie, chocolate chip, and tiny crumb - yum. Now zoom 1000x, taking tiny sized to arm sized, and they become 1000, 100, 10, 1 um. Call this microview, with microscopic microorganisms measured in micrometers. A grain of salt is sized like a cardboard box, a head hair like a hand-s…

There is a book from the 80ies/early 90ies "POWERS OF TEN: About the Relative Size of Things in the Universe" by Philip & Phylis Morrison. That is exactly that.

It's similar. There are several such continuous or 10x-stepped zooms, but a downside for education, is it's easy to lose context. Were viruses bigger or smaller than bacteria? Was Earth 10^6 or 10^7 m? Whereas, if you're asked say, how big is a glass of water, you're unlikely to say fingernail sized, or spread-arm sized - you've handled the item, and so now have a feel for how big they are. The 1000x chunking let's you leverage that. Once you've eaten red blood cell M&Ms, you know they are 10-ish..., err, ummm, not mm, not nm, so um. The Earth is a blue marble, so 10-ish..., err, mmm, not km, not Gm, so Mm.

A downside of 1000x steps is objects can end up inconveniently sized. 2 um zooms as either 2 m or 2 mm, often inconveniently large/small. Different zooms are good for different things. The small toy car scaled nicely for making roads, vs the larger toy car with moving doors; the small doll scaled nicely for making rooms, vs the larger doll with brushable-not-painted hair. Here, the 1000x step zooms are good for remembering and interconnecting sizes, but for then playing, you'll often want some other zoom.

Re: Ask HN: Teach me something new

#603

Post by vermarish »

spython wrote: post #503
vermarish wrote: post #225

An electric guitarist usually has a pedalboard that they use to make different guitar tones. Let's approach this like an electrical engineer might. Time is a straight arrow: call it t. The guitarist plays, and their guitar pickup records a signal. At any time t, measure the value of this signal's waveform: call it x. That signal can go into a pedal that maps each value to create an output signal. Call it f(x, t). The…

Could you link to these communities of people sharing impulse responses?

I thought I remembered a single platform where people upload their IRs, but I can't find it. I remember that one being too experimental for my taste. The best-sounding IRs are usually released in sets by a single individual, and mass-compiled in forums like these [0].

[0]: https://www.kvraudio.com/forum/viewtopic.php?t=107337&sid=44...

Re: Ask HN: Teach me something new

#604

Post by stevenhuang »

SemanticStrengh wrote: post #575
weberer wrote: post #441

Earlier quoted context omitted.

Can you share the explanation for the Nimitz incident?

I forgot the names, don't remember wether nimitz is gimbal but anyway that explanation is a great example of what kind of analysis we should do https://youtu.be/qsEjV8DdSbs

Counter claims exist for alternative flight trajectories that fit the data

https://mobile.twitter.com/the_cholla/status/151875157360987...

https://youtu.be/N9lOQkxMkW8

I would provide credence to the above flight path as witness testimony from the pilots themselves attest to it, while West's claims of it being just glare are on the data alone.

Nevermind West's continual assertions of it being glare when we have witness testimony that it's a fleet of objects moving together, including the Gymbal.

Re: Ask HN: Teach me something new

#605

Post by Beldin »

someweirdperson wrote: post #303
remus wrote: post #243

Earlier quoted context omitted.

Depends what you mean by a good reason I guess. A lot of very capable mathematicians have put time in to the problem and it's proven to be pretty resistant to a solution. I think problems like this often feel a little incongruous because they are so simple to state but so hard to solve.

It is easy, we can spit it into two parts: Proving that all even numbers end up in that loop and proving that all odd numbers do. I'll take the even ones. Who works on the odd ones?

I'll take a stab.

An odd number is a number that ends in 1, 3, 5, 7, or 9.

- ends in a 1: times 3 + 1: it now ends in a 4, which is even, and thus reduces to the even case.

- ends in a 3: tomes 3 is 9, + 1: ends in a 0; even again.

- ends in a 5: ×3 ends in a 5 again, +1: ends in a 6; again even!

- ends in 7: x3: now ends in a 1, +1: ends in a 2; even yet again!

- ends in a 9: ×3 then eens in a 7, +1 thus eens in an 8: even again!!

So all that's left is the cases for @someweirdperson ;-) @someweirdperson

Re: Ask HN: Teach me something new

#606

Post by pxeger1 »

someweirdperson wrote: post #334
pxeger1 wrote: post #145

Double-clicking on text selects the whole word. Double-clicking and dragging selects text word-by-word. Triple-clicking selects the whole paragraph. Middle-clicking a link opens it in a new tab. Middle-clicking a tab closes it. Middle-clicking in general often has useful functionality!

When holding the last click of the sequence multiple words/paragraphs can be selected. In some editors quad-click selects all. In code-editors tripple selects a line (hold to select multiple). When moving/deleting lines this is much more semantically clean (and faster) than manually dragging from the previous line's line end to the next lines last character before the line end.

> When holding the last click of the sequence multiple words/paragraphs can be selected.

When I wrote about the double-click-drag thing, I thought triple-click-drag might logically also be a thing, but it doesn't work for me. (Firefox, KDE, Linux)

Re: Ask HN: Teach me something new

#607

Post by mncharity »

Nick87633 wrote: post #66
mncharity wrote: post #6

Consider arm sized, hand sized, fingernail sized, and pinched-fingers "tiny" sized. About 1000, 100, 10, 1 mm. Tray of cookies, hand-sized cookie, chocolate chip, and tiny crumb - yum. Now zoom 1000x, taking tiny sized to arm sized, and they become 1000, 100, 10, 1 um. Call this microview, with microscopic microorganisms measured in micrometers. A grain of salt is sized like a cardboard box, a head hair like a hand-s…

Feels like a good VR experience or magic school bus episode would help solidify this! Or maybe time for this adult to make some dioramas.

Years back I was doing passthrough AR, and spiked a zoom to nanoview (atom beach and towering grain of salt; hardwired to a parking-lot view out my window). Was crude but fun. Intended to go to picoview, to demo a physically-realistic atom-bonding interactive, but it got put aside.

Magic school bus uses "zoom you", rather than "zoom objects". Tradeoffs, but one advantage of "objects", especially for chunked-zooming and AR, is you retain your environment to use as a size reference. Eg, "the red blood cell is M&M sized, and a grain of salt is cardboard-box sized, therefore the table, room, and playground are...".

Fwiw, my fuzzy recollection is someone wrote a simple VR zoomer in unity some years back. Re dioramas, you might find some inspiration from http://www.clarifyscience.info/part/Atoms (very slowwwwly loading page - wasn't intended to be public). I did outreach with a few 1 m diameter tables, each with assorted objects. Pool-noodle floats for hairs, Goodsell's molecular bio illustrations in nanoview, etc. Thought about how one might design a larger exhibit.

But I never did manage to find a community interested in this kind of thing, aside from scattered folks at MIT and Harvard. Size/scale is occasionally taught done down towards primary, and is taught in most every science and engineering curriculum. But knowledge of size/scale is rarely then used to teach other things, so there's little incentive to teach it successfully. With "well, that shouldn't come as a surprise, but oh my, yipes" outcomes.

Re: Ask HN: Teach me something new

#608

Post by goldenkey »

wonderbore wrote: post #507
goldenkey wrote: post #386

Earlier quoted context omitted.

Midnight Express gave me reason to believe it's other countries too like Turkey.

Isn’t Midnight Express an English movie? I’m not sure it can be used as source for that.

It was based on a true story:

https://youtu.be/2b5s0WBI8ug

Re: Ask HN: Teach me something new

#609

Post by sleightofmind »

tomcam wrote: post #51
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…

So why don’t we just put $100 trillion of that money into the economy? Why not just pay for everyone’s houses and college debt and personal debt this way?

There you go again. Asking a straightforward question in clear, comprehensible language, without any hand waving. How can you possibly expect the economic sophists to engage with you if you persist in this behavior?

Re: Ask HN: Teach me something new

#610

Post by jcims »

mijoharas wrote: post #362
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'd recommend the book "the man who mistook his wife for a hat" by Oliver Sacks which I seem to remember digs into some phenomonon like these. There are very interesting differences between certain lesions in the left side of the brain, and in the right side. For instance there are some people that are blind, but do not believe that they are, and vice versa, which lines up with your experience.

Oliver Sacks was always one of my favorites to hear on RadioLab. He was just a joy to listen to.
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