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Sunlight is yellowish in atmosphere since some blue's been scattered by the atmosphere[1], but it's white in space.

[1] https://en.wikipedia.org/wiki/Rayleigh_scattering


I don't think that's right. Sunlight is white in the atmosphere too. Scattering causes the sun, not the light, to look yellow, and so sunlight is thought of as yellow.


Scattering doesn’t really make the sun to appear yellow except when it’s low, behind a lot of air. When it’s above 30° or so it just looks blinding, neutral white (or non-blinding neutral white if there’s suitable cloud cover or other filter in front of it). Even though a lot of the blues are scattered around, the sun still looks just white when it’s high in the sky.

But when the sun does look yellow, its light is yellow too, that’s the definition of "looks yellow". And the golden hour paints everything in very iconic yellow-orange hues. The light as integrated over the whole sky is still white (modulo whatever’s scattered back into space), but the light that comes from the direction of the sun is clearly tinted yellow and the light from the rest of the sky is clearly tinted blue.


> But when the sun does look yellow, its light is yellow too, that’s the definition of "looks yellow".

Not quite; the sun is far away and is restricted to a tiny portion of the sky, but its light covers half the earth at a time. It is simultaneously true that the sun looks yellow and that the light we receive from it is white. It isn't the case that objects in direct sunlight are yellowed by that light; the yellow appearance when you look at the sun is something of an illusion.

> Even though a lot of the blues are scattered around, the sun still looks just white when it’s high in the sky.

This isn't true.


This is not universally applicable, especially if an algo isn't deterministic. For example if you were to time "bogosort of 100 items" you'd see increasingly better times the more runs you performed.


Or the now-ubiquitous footer:

"Store cookie? [Yes] [Ask me again]"


How would it know not to ask again if it can't store a cookie?


At least if this "Store cookies?" question is implicitly referencing EU regulations, those regulations don't require consent for cookies which are considered essential, including a cookie to store the response to the consent question (but certainly not advertising tracking cookies). So the respectful replacement for "Ask me again" is "Essential cookies only" (or some equivalent wording to "Essential" like "Required" or "Strictly necessary"). And yes, some sites do get this right.


I’ve not seen a site that remembers your selection of “reject all”/“essential only”. It would actually be hard to argue that it would count as an essential cookie, nothing about the site depends on remembering your rejection. I guess that makes “maybe later” more reasonable since it’s going to ask you every time until you relent.


"Reject all" doesn't have to be cookie, the answer could go to the browser storage.

Basically it just exists in your browser, telling it "the user didn't agree to cookies, so don't send this data and don't render those blocks". The only thing that web server knows is that requests come from someone who didn't send any cookies.

I believe it's a very common implementation.


Huh? Of course those get remembered, and of course it's allowed by GDPR. If the websites you visit don't remember "reject all", they're doing it maliciously (or out of incompetence, I guess).


It could know by respecting the DNT flag and don't even ask in the first place.


Pretty standard option for any home with a teenager, to be honest. Long enough to drag the handset into the nearest coat closet when needed.


Mom’s listening along on the other phone with her hand covering the receiver.


And of course, you can use the ~v / ~V commands (as listed in the ~? menu) to increase/decrease verbosity after the connection is established.

That lets you `ssh -vvvv` to a host then once you've figured out the issue use ~V to decrease verbosity so that debug messages don't clutter your shell.


I see this take a lot but I'd argue what Docker did was to entice everyone to capture their build into a repeatable process (via a Dockerfile).

"Ship your machine to production" isn't so bad when you have a ten-line script to recreate the machine at the push of a button.


Exactly my feeling. Docker is "works on this machine" with an executable recipe to build the machine and the application. Newer better solutions like OCI-compliant tools will gradually replace Docker, but the paradigm shift has provided a lot of lasting value.


Yeah docker codifies what the process to convert a base linux distro in to a working platform for the app actually is. Every company I've worked at that didn't use docker just has this tribal knowledge or an outdated wiki page on the steps you need to take to get something to work. Vs a dockerfile that exactly documents the process.


There's usually an easy-ish way to override malloc/calloc/realloc/free on Unix, as it's very useful to do when debugging issues or just to collect allocation metrics.

In ELF objects (i.e. on Linux) this is usually done with the "Weak" symbol binding. This is an optional flag for symbols in ELF format that let you override a symbol by providing a competing non-weak symbol, which the linker will prefer when there is a conflict. https://en.wikipedia.org/wiki/Weak_symbol

You can see the list of Weak symbols by looking for a 'W' in the output of `nm` on linux hosts.


> a search engine for search engines…

Everything old is new again: https://en.wikipedia.org/wiki/MetaCrawler


The ~ character for home directories was an old convention that dates from the ADM-3A (1976) terminal used by some early Unix users. The keyboard on that terminal happened to have the cursor control word "Home" on the "~" key. This shorthand was adopted by shells like sh/csh and emerged in HTTP urls as /~user/ being the shorthand for a user's personal web page on a site.

Much later in history Twitter popularized the form "@user" to refer to a personal identity. I'm not sure if they invented the usage or not. This is distinct, but probably somehow cognitively related, to the use of "user@host" for email addresses after bang paths fell out of favor.

For reasons I can't quite put my finger on @user seems a much better sigil than ~user to me, so I'm not bothered that it's become popular.


> For reasons I can't quite put my finger on @user seems a much better sigil than ~user to me, so I'm not bothered that it's become popular.

I think this makes sense if you pronounce the action. On Twitter you'd tweet [at] user(s). I think it made even more sense back in the Twitter via SMS where you had to send a message to Twitter's number but direct at a particular user.


It makes sense in a chatroom if you direct a message @someone (at someone), or if you direct a tweet @someone. So I guess the natural progression of that is @someone becoming the identifier.


Twitter was limited to what was easy to enter on a T9 keypad. Of all the available characters, @ was a good one to go with.


Look for the CRI rating of bulbs that you buy. It's a measurement of how close to a blackbody spectrum the bulb is putting out, the highest fidelity being 100. Note that this is not the temperature measurement, and you can have e.g. 2700K or 5000K bulbs with high CRI.

Newer LED phosphors are typically 90+ CRI, and I commonly find 93 CRI bulbs available off the shelf.

https://en.wikipedia.org/wiki/Color_rendering_index


Sunlight diverges significantly from a black-body spectrum because the atmosphere absorbs so many wavelengths.


I didn't want to mention that CRI is matched against the spectrum of _daylight_ because of the confusion that happens with color temperature when you mention the "daylight" word. You're right though, the CRI reference spectrum is matched against sunlight rather than a true blackbody.


Even high cri lights have a huge blue spike that doesn't match the sun. I don't know what chip OP uses, but you need a full spectrum light if you actually want very sun-like light. This page has some details:

https://optimizeyourbiology.com/best-natural-full-spectrum-l...

No idea if there's any evidence or not of the blue spike actually mattering for human biology.


Kind of what I worry about—the spectrum mismatch. Damn but incandescents sound pretty good for just this one application. I must be (am) getting old.


Interesting. The Wikipedia entry mentions SPD and I think that is where I think LEDs fall down—having a skewed and/or incomplete spectrum. Even though it may make certain target colors look correct.


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