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kloch

2,671 karma · joined September 1, 2021

Network Architect, Amateur coder

https://github.com/kevinloch/

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kloch··on Teaching ChatGPT to speak my son’s invented language
> you can supercharge accuracy to basically 100% for up to 13 digit addition and >90% after.

Is the ~13 digit limitation due to the model itself (how/how well it was trained) or simply the use of double precision in the model weights (which maxes out around 15 digits of precision).

kloch··on How To Get Started In Soldering
The most important thing: Put the heat where you want the solder to flow to, not where it's starting from.

This also applies to soldering/brazing copper pipes.

kloch··on C Strings and my slow descent to madness
> At first this looks great, but there is a problem. What happens when the source string minus the null terminator is as long as the size of the destination string? The answer is that the destination gets filled with all the characters of the source string with no room left for the null terminator.

The 'n' in strncpy is mainly there to help you avoid overrunning the destination, it does not guarantee whatever makes in there is null-terminated.

This is why you should always explicitly set the last byte to zero after using strncpy (and never ever use strcpy).

  char dest[16];

  strncpy(dest, src, 15);
  dest[15]=0;
kloch··on JWST gets best view yet of planet in hotly pursued star system
To ease the disappointment, here's an unrelated jwst image that was released today: https://esawebb.org/images/potm2303a/
kloch··on Zero one infinity rule
One example I recently ran into with large image files, specifically a 24GB PNG file, which of couerse requires much more working memory when uncompressed:

Gimp: Opens this image successfully without complaining. It takes a while and uses lots of swap space but it works.

OSX Preview App: "The file <filename> could not be opened. It may be damaged or use a file format that Preview doesn't recognize.

So not only does Preview fail to open the file, it also lies about what the specific issue is. Apparently nobody at Apple ever imagined opening such a large file.

The early Internet flourished in large part because the protocol designers correctly recognized that they couldn't predict or even imagine all the ways people would use their work. "Be conservative in what you send but liberal in what you accept - John Postel" https://en.wikipedia.org/wiki/Robustness_principle

kloch··on Ask HN: Is Hacker News slow for anyone else?
That was definitely a thing back then. I've had sites slashdotted several times and never had any issues using FreeBSD and static-ish content and/or compiled C cgi's w/mysql. It also helped that I worked in networking and always had (sometimes just) enough bandwidth available.

Then there was that time in my Atari 800 was slashdotted. The Atari could serve several hits/s on it's 9600 baud interface but the 3com CS-210 terminal server would crash about every 6 hours. https://kl.net/atari/

Probably the most surprising (for it's time) hits/s I had to deal with was when Art Bell had my solar status monitor gif's inlined right on his homepage for a while in 1997-98. It was pretty wild when he would say on the air "Go to my website right now!"

kloch··on Improved audio rendering with an optimised version of memcpy (2013)
> no digital harshness

Reminds me of comments when CD's came out int he 1980's. Audiophiles and magazine articles insisted they could "hear the aluminum".

What they were actually hearing was songs mastered for Vinyl or casette that had not been properly remastered for digital. Vinyl and casettes required pre-emphasis of highs to offset the limited high frequency response and noise of analog media.

kloch··on The Evolution of Motorola Phones
The first cellphone I bought was a Motorola Alpha https://www.mobilecollectors.net/phone/3802/motorola-microta...

I thought it was odd - and a bit misleading that it had the words "Digital Personal Communicator" on the box. I knew it couldn't communicate digitally but it did get me to imagine what that would be like.

I assume digital referred to the storage of phone numbers + names which was a novel feature at the time. The display wasn't seven segment LED like previous versions, it had low-res green dot matrix LED arrays that could display a few crude alphanumeric characeters.

kloch··on SUVs emitted more carbon dioxide last year than most countries
As a side note, this video has a great variety of historical footage of cars/cities/life.
kloch··on SUVs emitted more carbon dioxide last year than most countries
> they're safer when it snows and winter

Are they actually safer or do they just give the driver a false sense of security? Assuming it actually has 4WD/AWD (and most don't), that only helps you "go" and does nothing for "stop" as all cars have four wheel brakes.

One exception to this is being able to keep going in very rural areas where any rescue attempt would take too long. However, even this can fail with a false sense of security and poor judgement:

https://www.11alive.com/article/news/nation-world/man-strand...

> Of the dozens of missions we have had this winter involving a vehicle stuck in the snow, nearly all of them were 4x4 vehicles and almost all of the drivers told us, "I didn’t think I would get stuck."

I've found that EV's have a significant advantage in snow due to very precise torque control compared to an automatic or manual transmission. Even my Prius does surprisingly well in snow with fresh tires up to it's ~6" ground clearance.

kloch··on The Office as Architectural Touchstone (2008)
This site is the birthplace of Radio Astronomy

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

kloch··on Room-temperature superconductor discovery meets with resistance
> Reactions by 10 independent experts contacted by Quanta ranged from unbridled excitement to outright dismissal, with many of the experts expressing some version of cautious optimism.

This is exactly how an arbitrary group of scientists should react to extraordinary claims like this. Not 100% dismissal because of the history or provenance of the researchers, not 100% acceptance without independent replication.

kloch··on Room-temperature superconductor discovery meets with resistance
This is exactly the kind of thing the patent system was intended to prevent. You have to share enough details of your secret sauce so others can replicate it, even if you intend to not license it or charge outrageous licensing fees. That way the knowledge is out there today, can be expanded on by other researchers/inventors, and at a specific date in the future anyone can use it.

It also helps reduce fraudulent claims of new discoveries.

kloch··on The floppy disk just won’t die
Thanks, now I feel really old.

Seriously though, until very recently you could hear dot matrix printers at most airline gates. They used them to print out manifests to hand to the crew right before the plane departs.

kloch··on The floppy disk just won’t die
> Davit Niazashvili, a maintenance manager at Geosky, a cargo airline based in Tbilisi, Georgia, still uses floppy disks to apply critical updates to two 36-year-old 747-200s, which were originally delivered to British Airways in 1987:

GeoSky frequently lets youtubers film in the cockpit of their 747-200's. If you are a fan of the classic 747 steam gauge cockpits, these videos are priceless. Some examples:

Classic Boeing 747-200 Clock Shop! Geo Sky Takeoff from Tbilisi, Georgia, to Frankfurt! https://youtu.be/JSKYoqVPtWw?t=88

BOEING 747-200 Takeoff | Less than 10 B747 Classic still flying now! https://youtu.be/O8AA_tkY49g?t=503

kloch··on Today's 5-year-olds will likely live to 100
"It's the year 2000, but where are the flying cars? I was promised flying cars!"

https://www.youtube.com/watch?v=vzm6pvHPSGo

kloch··on Earth’s innermost layer is a 644 kilometer wide ball of iron, new study finds
Are you sure? It's about the same temperature as the surface of the Sun.

That means if you could see it, it would also be as white hot as the Sun seen from Space.

kloch··on Why dark matter feels like cheating (and why it isn’t)
being "skeptical of throwing full confidence at option 2 " is not the same as "demanding it be thrown out". It just means show us something more than "magic variable 'X' fits all curves."
kloch··on Why dark matter feels like cheating (and why it isn’t)
> For dark matter, we keep those standards. The evidence for some kind of dark matter, that there is something that can’t be explained by just the Standard Model and Einstein’s gravity, is at this point very strong.

Option 1: Do more research on Gravity to see what we might be missing there. The difficulty in measuring G, and the flyby anomaly would be good places to start.

Option 2: Make up fully unconstrained variable 'X' that can take any value you want at any location or time in the universe[1]. This is amazing because it can perfectly solve so many difficult problems!

Obviously many people will and should be skeptical of throwing full confidence at option 2 in it's current state.

[1] Unlike neutrinos or black holes, there is no theory for what dark matter is made of, and how it is created or destroyed. Thus there are no constraints on how much you can have at any given location or time.

kloch··on Show HN: I trained an AI model on 120M+ songs from iTunes
This works really well!

Could you add links to play songs on Spotify?

kloch··on How do we see color?
For software engineers wanting to know more about this subject I highly recommend this article:

https://en.wikipedia.org/wiki/CIE_1931

Human color vision is a lot more complicated than it seems at first. The sensitivity curves of the actual receptors in the eye do not directly match our physiological perception curves for red, green, and blue. The red perception curve even has some negative (!) values. There is a lot of neurological processing involved and that is why colorspace models are so complicated and imperfect. There is no simple absolute "RGB" mapping like I and many others have naively assumed before digging into it.

kloch··on Connecticut parents arrested for letting kids walk to Dunkin' Donuts
When I was a kid in the 70's/80's we weren't just allowed to play outside unsupervised until dark - we were required to!

There was an arrangement where the older neighborhood kids would look after the younger ones.

kloch··on Easter egg in flight path of last 747 delivery flight
It wasn't even a 707, it was a prototype model 367-80.

There were some unusually significant structural differences between the prototype dash 80 and production 707's, for example:

> The 132 in (3,400 mm) wide fuselage of the Dash 80 was large enough for four-abreast (two-plus-two) seating like the Stratocruiser. Answering customers' demands and under Douglas competition, Boeing soon realized this would not provide a viable payload, so it widened the fuselage to 144 in (3,660 mm) to allow five-abreast seating and use of the KC-135's tooling.

https://en.wikipedia.org/wiki/Boeing_367-80

https://en.wikipedia.org/wiki/Boeing_707

kloch··on WAN router IP address change blamed for global Microsoft 365 outage
> As part of a planned change to update the IP address on a WAN router, a command given to the router caused it to send messages to all other routers in the WAN, which resulted in all of them recomputing their adjacency and forwarding tables. During this re-computation process, the routers were unable to correctly forward packets traversing them. "The command that caused the issue has different behaviors on different network devices, and the command had not been vetted using our full qualification process on the router on which it was executed."

From this it sounds like they might have changed the primary loopback IP, which by default is the "router-id" for various routing protocols, causing the entire network to have to reconverge. You can override the default router-id with an explicit address that does not depend on lo0 but lots of networks don't do that.

It's extremely uncommon to change the primary loopback address. It's less uncommon to add an additional one but as the article says that syntax varies by vendor: Juniper will add as additional by default, Cisco and Arista will replace the existing primary one (IPv4) unless you include the "secondary" keyword...

kloch··on Electrify America “fries” EVs at charging stations
This is particularly disturbing because often EA chargers are the only reliable fast chargers around for CCS, so it's not like you can just avoid them for another network on a long trip.
kloch··on Astronomers discovered 1M new galaxies in 300 hours
JWST has unmatched sensitivity for galaxy searches but a fairly narrow field of view. To cover the same area as this survey (whole southern sky) would take about 15 million JWST frames.
kloch··on A dinosaur with a remarkably preserved face
I wouldn't read too much into that, hairless cats and plucked birds look very different from their fully dressed versions.
kloch··on Contracts you should never sign
The author ignores an important part of the negotiation equation - are you being adequately compensated for the imposed limitations?

For example a one year non-compete after separation might be unreasonable by itself, but coupled with one year of full severance pay is a different story, although there is still the "what am I supposed to do with my time?" issue.

If you are a founder/early employee with significant equity then a non-compete clause when being acquired will likely be acceptable to you.

kloch··on The contagious visual blandness of Netflix
There is some small truth to this - at least for image acquisition. The bayer filters in modern digital sensors are way to broadband, which perhaps counterintuitively reduces saturation, but more importantly reduces color accuracy from human perspective. This is especially apparent in the green-red spectrum.

The sensitivity curves of Kodachrome 64 and presumably 35mm film stock much more closely match CIE 1931 effective bandpass curves and results in much more accurate color.

However, most this can easily be fixed in post with modern tools. Almost all of what you are seeing today is artifacts of the Director/cinematographer/editor's artistic choices and not the acquisition tech.

kloch··on Interesting Facts about Bell Labs and 2001: A Space Odyssey (2001)
> The article discusses the picture-phone in 2001 as if it's commonplace technology today, but it really isn't. It's available, but people don't actually use it much outside of Zoom meetings for work.

Before Covid this was definitely true. However, since early 2020 there has been a significant trend of people turning their cameras on during conference calls. And not just for work, my local AFOL club has weekly zoom meetings where most participants use video. Family members will sometimes do a group video chat on FB.

I likely participate in more video calls per week than sci-fi writers and scientists of the 1960's imagined, mainly because the incremental cost today is zero (we pay for it whether we use it or not).

> people now prefer to communicate solely by text message, so we're effectively going back to something like a fancy telegraph.

While true, I don't think that makes video calls an irrelevant novelty.

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