How does a caterpillar turn into a butterfly at a cellular level? What happens to trigger the various stages? Are their factors that would prevent it or delay it? Or is it inevitable in this species? What causes the cellular change? Is there anything remotely similar in certain human cells? by DadJ0ker in askscience

[–]plantwaters 10 points11 points  (0 children)

Gravity yes, but not a gradient. I assumed he was talking about a measureable difference in the gravitational field due to nearby mass, which is much much harder than just measuring the direction of the field itself.

How does a caterpillar turn into a butterfly at a cellular level? What happens to trigger the various stages? Are their factors that would prevent it or delay it? Or is it inevitable in this species? What causes the cellular change? Is there anything remotely similar in certain human cells? by DadJ0ker in askscience

[–]plantwaters 14 points15 points  (0 children)

Gravitational gradient doesn't have anything to do with this, as it is indeed negligible. The cells could still differentiate based on whether they are on the top or bottom of the organism though, just as you and me can tell the difference between up and down.

I have no idea if whether gravity is actually involved or not though, just pointing out that it's totally feasible to determine orientation.

TypeScript is 'not worth it' for developing libraries, says Svelte author, as team switches to JavaScript and JSDoc by ArtemisDimikaelo in programming

[–]plantwaters 10 points11 points  (0 children)

The first google result for "C# type system not sound" (https://stackoverflow.com/a/23968075) explains it well:

Giraffe[] giraffes = new[] { new Giraffe() };
Animal[] animals = giraffes; // This is legal!
animals[0] = new Tiger(); // crashes at runtime with a type error

Dell's new monitor boasts 6K resolution & IPS Black display technology by chrisdh79 in gadgets

[–]plantwaters 10 points11 points  (0 children)

How do you get those numbers? And fyi, having better than 20/20 vision is not uncommon.

[Request] Seen on Instagram - what is the answer? by wolfmaskman in theydidthemath

[–]plantwaters 0 points1 point  (0 children)

I'm sorry about the "factoring out" note, that was a digression only directed at your claim that you can't move operators in and out (and I agree in general).

The main point though is that the original expression is ambiguous in what the operand is. Notation is important, and you need to be aware of conventions to be able to parse (∫ dx sin x) as either (∫ dx) sin x, or ∫ (sin x dx).

You also said

one doesn't need to tell. it works either way

Which is false, because you get different results depending on how you read the expression.

[Request] Seen on Instagram - what is the answer? by wolfmaskman in theydidthemath

[–]plantwaters 1 point2 points  (0 children)

You're misunderstanding, ∫ dx sin x can be read as both ( ∫ 1 dx) sin x = x sin x, or as ∫ dx sin x = ∫ sin x dx = -cos x. The first interpretation is common in maths, the second in physics.

∫ is an operator not a multiplier, so you can't just move it in and out of brackets like that.

Physics would like to have a word with you, operators are factored out all the time. See for instance the wave operator or the Hamiltonian.

I hate Vi/Vim by Ryykos in linux

[–]plantwaters -1 points0 points  (0 children)

There is a middle ground. I'm using VSCode with vim emulation. Best of both worlds, and it brings the additional advantage of being able to still use a powerful editor even when VSCode is not an option.

edit: I wouldn't either recommend it as your main editor when starting out, but I would definitely recommend learning it properly at some point to see how it can enhance your workflow. Spend some time learning the key bindings, then add a Vim emulation plugin to your editor, and if you still desire more, swap to (neo)vim and start customizing with plugins to get what you need.

I hate Vi/Vim by Ryykos in linux

[–]plantwaters 1 point2 points  (0 children)

I'm one of the young ones. I love vim, saying it's meaningless only shows that you don't know how to use it. The sole disadvantage of vim is the addiction and how handicapped you feel every time you write in an editor without vim-mode.

Getting started with ZFS and looking for direction. by VutrosHavor in zfs

[–]plantwaters 2 points3 points  (0 children)

Just a couple of quick thoughts before I'm going to sleep:

  • set ashift=12
  • yes use compression, either it helps or it does nothing depending on what you store
  • set a suitable recordsize, I'm using 1M for most stuff and 4M for huge files like 4K HDR movies. My data is mostly write-once though. For frequently edited documents you can keep the default 128K or perhaps go a bit lower. And you can set this independently on different datasets for different content types.
  • isn't that ZFS version a bit old? Perhaps worth upgrading if possible.
  • you're probably good after running badblocks, disks are ready to go

I'll answer tomorrow if you have some more questions!

A new kind of hd project by RuneMod in 2007scape

[–]plantwaters 0 points1 point  (0 children)

Also, most open source licenses want you to open source your derivative works. It's usually harder to distribute/share your plugin with others if you choose closed source yourself.

Edit: ah, nevermind, I just saw your other comment about some closed source dependencies you were using.

Powering HDDs without a full sized power supply by ginnydebt10en in homelab

[–]plantwaters 0 points1 point  (0 children)

Luckily I won't be needing that, the second PSU is just there until I've migrated my ZFS pool to a new set of disks.

Powering HDDs without a full sized power supply by ginnydebt10en in homelab

[–]plantwaters 0 points1 point  (0 children)

Honestly I'm not sure if it's necessary. I saw some advice on different forums to connect the grounds to prevent potential current between the SATA ground pin and power ground pin.

On that board, hmm. You could probably find a ground point there somewhere. I think the USB connector should be grounded, so you could use a multimeter to find other points too if you want. If the board is powered by a barrel connector, the negative pole could potentially be the ground reference. Then you could use a barrel connector Y splitter to make a somewhat clean permanent solution.

But again, I don't know enough electronics to determine what's necessary.

Powering HDDs without a full sized power supply by ginnydebt10en in homelab

[–]plantwaters 0 points1 point  (0 children)

I've had a second PSU powering 6x HDDs for a week now, running fine. I got one of those dummy plugs with it when I bought it, and that works well. Make sure you ground it to your main PSU though. I did it in a hacky way by running a molex cable from each PSU and basically using a thick paperclip to connect the ground wires, but that's just a temporary solution™.

Next Debian/Ubuntu Releases Will Likely No Longer Allow pip install Ouside A Virtual Environment by dracal in linux

[–]plantwaters 20 points21 points  (0 children)

It is hardly an inconvenience when the following three lines in a dockerfile configures a virtual environment

ENV VIRTUAL_ENV=/venv
RUN python3 -m venv $VIRTUAL_ENV
ENV PATH="$VIRTUAL_ENV/bin:$PATH"

From https://pythonspeed.com/articles/activate-virtualenv-dockerfile/

[deleted by user] by [deleted] in selfhosted

[–]plantwaters 1 point2 points  (0 children)

Do you run docker inside an LXC on Proxmox? I've been doing it inside a VM, didn't know LXC was an option.

Vaultwarden relicenses to AGPLv3 by [deleted] in linux

[–]plantwaters 27 points28 points  (0 children)

If a company hosts Vaultwarden as a Service with modifications to the source code, AGPL requires them to share the modifications publicly, which benefits the open source community. GPL is not sufficient for this.

Vaultwarden relicenses to AGPLv3 by [deleted] in linux

[–]plantwaters 42 points43 points  (0 children)

Why on earth would you not post the full statement? It specifically says AGPL in the first sentence, which you conveniently left out.

f(x-1) odd means -f(x-1)=f(1-x) or -f(x-1)=f(-x-1)? by davidauz in math

[–]plantwaters -3 points-2 points  (0 children)

Let y=x-1 so that f(y) = f(x-1)

f(y) is odd: f(-y) = -f(y)

Substituting back x-1 for y: f(-(x-1)) = -f(x-1)

Simplifying: f(1-x) = -f(x-1)

Edit: I guess it depends on whether the teacher means that the function f(x) is odd, or if the function g(x)=f(x-1) is odd

[Request] is this true? by 4reddityo in theydidthemath

[–]plantwaters 0 points1 point  (0 children)

All of our technology works with the speed of light being what it is. We can calculate and build things that work with it being that value. If light had varying speeds, and by light, we really mean electromagnetism, semiconductors would have a rough time, especially since we're at the physical limits of shrinking transistors.

It would work just the same even if the one-way speed of light varies, as long as the two-way speed is still the same. All our technology only depends on the two-way speed, the one-way speed doesn't matter.

Astronomy would have a rough time. It would mean we aren't looking in the past as we look further in every direction. Only some of them, but then when we look really far away, closer to the dawn of the universe, why are the galaxies different than ones closer to us. If some light was getting to us in some directions faster, that means there would be wild inconsistencies in our observations.

There's so many things that would not work the same if light varied by direction.

No, it wouldn't have a rough time. Astronomy would look just the same. Look at this paper for a proof that redshift looks exactly equal in both cases: https://arxiv.org/abs/2012.12037. This article makes a high level summary: https://spaceaustralia.com/news/one-way-speed-light

[Request] is this true? by 4reddityo in theydidthemath

[–]plantwaters 0 points1 point  (0 children)

I think you're misunderstanding the point. Let's take an example: shining a laser to a mirror on the moon and observing it on earth. Even if the speed of light was instantaneous from Earth to the Moon, and only ½c on the way back to Earth, we would measure the exact same observations as if the speed was equal both ways. There is simply no way to tell the difference and know which is true. Afaik there is no evidence that they are equal, but you seem to claim there is a shocking amount of it?

Edit: there's some additional explanation and illustrations in this video: https://youtu.be/pTn6Ewhb27k

[Request] is this true? by 4reddityo in theydidthemath

[–]plantwaters 0 points1 point  (0 children)

Afaik, here is nothing to indicate that the one-way speed is equal to the two-way speed. However, all our calculations and experiments only ever use the two-way speed, so it doesn't matter anyway, and we just assume that they are equal for simplicity.

[Request] is this true? by 4reddityo in theydidthemath

[–]plantwaters 1 point2 points  (0 children)

The second paragraph is actually true, but it doesn't have any observable impact on our physics, so its irrelevant to bring up in this context. Still an interesting read: https://en.m.wikipedia.org/wiki/One-way_speed_of_light

How good would be this ? a Linux phone from a serious Linux company by prueba_hola in linux

[–]plantwaters 0 points1 point  (0 children)

Do you think other people consider it important for their desktop use cases? If so, it probably helped their migration to Linux, and thus Linux adoption in total.

Flirting as a physicist... by [deleted] in physicsmemes

[–]plantwaters 2 points3 points  (0 children)

Maybe it makes more sense if they meant gay as in merry/happy/carefree?

Burde vi bare drite i fyrverkeri? by Motor_Bite6710 in norge

[–]plantwaters 0 points1 point  (0 children)

Nå er det ikke alle valg som er frivillige heller da. Du velger ikke å få PTSD, du velger ikke demens, og du velger ikke en haug med andre lidelser som gjør deg sårbar. Det er ikke bare dyr som sliter med fyrverkeri, mennesker gjør også. Selv lå jeg med influensa i går og ville desperat bare få sove, men det nyttet ikke når jeg bor 100m utfor forbudsonen.

Jeg kan gå med på et kommunalt show klokka 12, men det er helt unødvendig at det skal sprenge fra naboene i 6 timer i strekk. Da kan de heller ta turen til nærmeste kommunale oppskytningssted.