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downut

794 karma · joined August 22, 2016

Inactive c/c++/java/ruby/fortran/awk/perl/(c)make/bash/csh hacker. I got paid well to work in all of them.

rcarter@pinyon.org

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downut··on AI use leads UC Berkeley math professor to see 'no point' in grading homework
I am so sorry it is this way now. I personally believe if you have imposters in the class who intend to learn nothing it degrades the experience even for the highly motivated. Humans want to be in incentive-aligned learning experiences.

I had one fellow in the back of the room at UF in the basic algebra 1 course(!) who began the semester by once or twice a class doing a reasonable impression of a mooing cow. I kicked him out. Didn't happen again. Classroom atmosphere had better vibes after that.

downut··on AI use leads UC Berkeley math professor to see 'no point' in grading homework
Why would you grade math homework? I taught "intro math"[1] through algebra and calculus to linear algebra at UF and ASU over four years as a paid graduate TA. This was the middle '80s. I assigned homework from the text every class. At the beginning of every class we (the students and me) worked through any particular problem any student wanted. That was 15min, max. Then I lectured and assigned more homework. I graded my own 3 in-class closed-book exams and final exam.

Based on the classes the Math Department gave me (very satisfying) and the student evaluations this seemed to work more or less fine. I was a brutal grader though, some of those entry level classes had bimodal distributions with 'F' being the low mode.

I also showed up for office hours and did my best to help people learn by digging through their questions.

I don't see why this methodology wouldn't work fine today. I wouldn't care now how a student learned. Show competency on the human only test and we're good.

I had one student who achieved a solid 'F' come by office hours after the course to tell me how much he enjoyed my teaching. Whatever!

Anyway, teaching that way, with the positive interactions with students interested in learning, was one of the greatest experiences of my life.

[1] An absolute pedagogical shitshow that wasted everyone's time for zero gain.

downut··on Airbnb bans making guests do dishes and take out the trash
AirBnb is camping. I have been travel camping with and without people for 50 years. The longer you camp the better the experience. Almost all of the first 25 years involved a tent (or bivy sack), and maybe a camp kitchen. Then you surface again, happy minded, into a world where people travel but they expect everyone touching their utensils or even maybe food(?) have a "Food Handler's card or certificate". Whatever that is. Back into the bush.
downut··on There's never been a better time to go into math (by: 3blue1brown) [video]
I started grad school at math in Sept. 1995 and:

"There's never been a better time to go into math" was the final statement of the ten minute orientation session from the Dep Chairman.

It was a great thing to do anyway.

Then.

downut··on The Intel 8087 chip: floating-point addition and subtraction
Ah. So now we are talking about multi-precision libraries, which their basic reason for existing is that different precision formats yield different economically interesting results, via a variety of a not-large set of economically interesting tradeoffs.

The 80 bit format was an at-the-time (ATT) engineering optimization that made ATT double precision (DP) more attractive given the better round-off behavior, at "no-cost".

So the interesting question here (that I don't know) is: is "deterministic" quad-precision (QP) as the accuracy upgrade from "non-deterministic" 80bit internal DP, always better economically?

Depends on what the computational problem is, given a budget. And that budget buys things that are only available on the market.

I used to think technology monocultures were a good thing but given the current state of things I have reversed myself. I am happy that life has simplified for you though.

I've been watching, lightly, interval arithmetic for 40 years. As you know algorithm sensitivity information is mandatory. We used intel 80bit FP do evaluate that, slowly, back in the day. We didn't use interval arithmetic, though we knew about it. It wasn't economically viable. Hey C++ what can you do for us? Templates, damn.

How important is interval arithmetic, economically, now?

downut··on The Intel 8087 chip: floating-point addition and subtraction
TY. I am ignorant of the compiler side of the process here. My mental model as a former numerical algorithms guy at the time was that the x87 chips performed the 80 bit operations as opaque internal operations, and returned the visible results back as 32/64 bit IEEE754 floating point format bytes.

Is that inaccurate? If not how did you store the extra 16 bits (DP)? I should've bought a zortech compiler back in the day? ;-)

I am sorry that Borland hooked me with turbo-p and then jacked me up with turbo-c/c++.

downut··on The Intel 8087 chip: floating-point addition and subtraction
Aha! TY. Sun's floating point people were world class but I still think this was a dumb thing to do.

With the NAS Parallel Benchmarks we were trying to encourage as wide a diversity of hardware and algorithms as possible so we were lenient with the acceptable "valid" interval of "correct" behavior. I've already discussed heretical Cray FP. Those were fantastic systems. No way would we disqualify some weird/different algorithm/architecture if it meaningfully advanced the SOA in performance/efficiency. OTOH wars were fought over having any firm accuracy requirements at all. So this jvm thing looked... pointless at best?

This is all nostalgia for a past that actually was. Those were the days my friends.

downut··on The Intel 8087 chip: floating-point addition and subtraction
"numerics people ignored it"

I dunno Walter but as the first(?) IEEE754 implementation in a PC system it seemed like a pretty damn big deal to us people working in numerical algorithms. It was a big enough deal to me at the time (I was in graduate school) that I've kept my 8087 chip all my life and have it before me now. I see the old boy has lost a pin during the last move, dammit.

Chip has "3716150AA MALAY BEV 22" embossed on the pin side. Search gets me nothing.

downut··on The Intel 8087 chip: floating-point addition and subtraction
The 8087 came out when the premier numerics processors worldwide were the various Cray/CRI products, and if you know this much about the 8087's extended register format then it's likely you already know about Seymour's opinion expressed in silicon about the handling of the LSBs. As a freshly minted computational mathematician I was worried about the Cray systems accuracy on long running computations but after 5 years right on the front lines of the 1-4 highest throughput systems worldwide, with, ISTR, zero practical effect on any computation that ever mattered. Huh turns out Seymour was smarter than me. Should've picked up a shovel.

As far as delivered accuracy of the 8087, performing the operations at 80 bits, rather than 64 it was better than non-extended formats. Anyway you can read all about it here:

https://en.wikipedia.org/wiki/Extended_precision#x86_extende...

Kahan endorsed is all I needed to know.

I can't remember the details from back then but the initial Sun java implementation did something weird with this.

downut··on Florida's HOAs and condo associations are making the housing crisis worse
I just went to zillow and typed in my zip and tried two different filters for single family homes priced between $300K-$550K:

Listings:

No HOA fee: 32 up to $500/month: 62

I'm not going to bother because this is an HN comment but I think you can imagine what happens to the results when I specify newer than say 1993 (when my house was built).

I have an HOA, but it seems defunct. Everything we do to the house, if visible, can be interpreted to mean I must get unanimous agreements, in writing, from all my neighbors.

It turns out I managed to land right between two asshole neighbors (constant trespassing, dogs, etc)

downut··on Someone on Torrent Sites Kept Fucking with My Sonarr
Ok, I have not indulged in the new paradigm of work your way to the interesting stuff. I just did occasionally dabbling back in the day, but I wonder: I fully understand the intent of making a prospective good citizen demonstrate commitment and the level of service-side management effort to make this social network paradigm work.

But isn't this sort of structure just completely transparent to [Nation|Narco]/State Actors? Feel free to widen the set of economically interested actors.

How do you scale video interviews?

I think I am missing something about this scene. I really want to dive in tho.

downut··on The Copilot+ PC brand is dead
Can't you replace the keyboard? (I'm assuming "workstation" != laptop). I have mechanicals laying around that I would just haul with me into work.
downut··on Jury finds Facebook liable for deceiving users in Cambridge Analytica case
"... seems to be ..."

Compared to what? Your string of comments are banal generalities that may or may not apply to this particular situation. Where else in this world at this time, is this particular governmental failing handled materially better?

Singapore? China? Russia? Switzerland? England?

I have sometimes learned interesting things from you (as a commenter) but there is nothing to learn here. It appears to be only diversion and distraction.

downut··on Disney+ and Hulu raise prices by up to 13 percent after doubling profits
"here"

It's a big world out there, whatever "here" means.

That last sentence makes me wonder, do you enjoy ads?

I went to a Super Bowl party a while back and the half time show glitched continuously. Random weird glitches for the rest of the time. => note to self: don't pay for this.

downut··on Samsung accidentally freezes its smart fridges with a software update
Huh, two houses back I had a really fucking POS dryer that I got expert at replacing the "Dryer Thermal Fuse" (pick your own youtube video walkthrough) and my foggy memory says in my ear that it was an LG dryer. So I'm thinking, this commenter malfist, doesn't know what he is talking about and I'll go look in my notes.org and... NOPE! It was a Samsung DV42H5000EW/A3 model!

Sorry malfist for thinking bad thoughts. I've redirected all that negative energy back to its rightful owner: Samsung.

The washer next to that dryer was an LG, and in my notes I never touched it.

Always good to reattach to reality.

Ah, I see that the washer/dryer pair we bought new 4 years ago and hauled across the country are LG ThinQs. Very happy with them. Apparently can be "smart" but I shut that down.

downut··on Singapore’s National Library Board offers micropayments to build reading habits
It is in actual fact not difficult to "drop communication with for hours at a time". This was the human norm for millenia, up to a decade or so ago. And given the toxic side effects of all this communication it's probably going to have to be worked out again.

We raised a child with the principle that "No News is Good News". She turned out great! And she lives that way still. That constant level of screen stimulation is strictly not necessary for family happiness, and I think you all who think so have not really internalized what it means for a child to learn responsibility.

See also free-range kids, and the social insanity that causes kids/parents to get arrested for eg playing in a park alone. There's a bunch of mental illness out there, and the screens are big reason why.

Oh right. My beautiful daughter reads books constantly. Weird that, huh.

downut··on Great Lakes sturgeon may be 400 years old:Scientists rethinking how to save them
It's perhaps not intuitive but it turns out organized anglers have been a big part of rescuing various fish populations. For instance, as a member of the "Backcountry Hunters & Anglers" group me and about 20 other members hiked up the West Fork of Oak Creek in Oak Creek Canyon AZ with heavy backpack tanks filled with (formerly) endangered Apache Trout fingerlings. It was absolutely wonderful to watch the little ones swim away. Trout Unlimited has a ton of conservation efforts including habitat, which helps viability of a whole bunch of other species.

Similarly, you can read the book "People of the Sturgeon: Wisconsin's Love Affair with an Ancient Fish" to learn about how the people around Lake Winnebago came together to restore the health of its native Sturgeon population.

This idea of "othering" human beings apart from the animal world might sound like the most effective way to "help" animals but humans, being complicated, don't work that way.

I couldn't care less what you eat, if it makes you happy, awesome. But there's a whole lot more going on culturally with conservation that is entwined with the evolved nature of human beings.

downut··on All grown-ups were once children, but only few of them remember it
The concepts TT describes are very patiently and pleasantly explained in the recent book "The Score", by C. Thi Nguyen.
downut··on Ask HN: Are others seeing Google's reCAPTCHA rejecting Firefox users?
Ok, debian forky, 155.0.1, successfully logged into vultr.com after a year inactive, added a credit card and a little credit. I do, however, still stupidly use google authenticator for 2FA. The captcha was just a checkbox.

That said I have run into a number of unsolvable captchas lately on firefox. Had to use chromium on a healthcorp insurer site.

downut··on De-Brainrot Vacations
It's possible that I'm in your grandparent's generation, or maybe your parents. I'm 65. I don't want to derail the conversation, but I do want to correct the bit about "exercise as a hobby was viewed as extremely weird, runners used to be arrested!". In the '70s at least, running was extremely normal. Endurance bicycling was normal. For instance, starting in 1979. I bicycled all over the South: FL GA NC, at least. These were then as they are now quite provincial from the POV of alternate ideas. 10K runs were a thing, with thousands of participants. As were Marathons. Cross country running was a popular high school sport.

If you want to talk about work, well I'm adjacent to 5th generation farmers. Self driving climate controlled machinery is a thing now, but! hard to imagine I know, people had tractors back then too.

So, plausible as it might sound to ascribe some of the causality to flow from "the physical activity transition", I don't think it holds up.

downut··on AI handles incidents, engineers lose touch with their systems
Suppose "Reflections on Trusting Trust" is not the naive rantings of some obsolete dinosaur.

Why does it not apply?

downut··on Europe's summer drought is so extreme that desertification is a growing threat
My wife and I retired to Tucson last year, and intentionally went through this first summer just to get the full experience. Never again! We've been under flash flood warnings the last several days and have only had a few sprinkles to go with the 108F days.

So... I had a look at Eureka CA weather this morning. Looks like Western Norway. Nice. Spending July and August up there might be mandatory for our mental health.

We spent 3 years in Tempe back in the '80s. It sucked then too.

downut··on Gödel, Escher, Elisp: The Beauty of Macros
Suppose I accede to every claim you make here. Where may I see the advantage in the long run, in any dimension? I'm willing to go with hearsay.

The word "dimension" is chosen to be so vague that you can surely do it. I would be easy to impress.

downut··on New Worlds: We are living in the future of J.G. Ballard or William Gibson
Stand on Zanzibar was so prescient it gave me goosebumps when I read it 5 years ago.
downut··on Gödel, Escher, Elisp: The Beauty of Macros
Ok, common-lisp newbie here.

Could you explain why Paul Graham's book "On Lisp" is wrong? Or misguided? Or misunderstood by newbies like me? 30 years of c++ with a lot of dealing with templates and I'm not feeling the mandatory function purity here.

downut··on GLM-5.2 – How to Run Locally
I am fascinated that I got down voted. I mean, isn't what I'm doing here nearly ideal? Or maybe not: why? My solar panels shade my roof under the incessant sun of the Sonoran Desert and turn a fraction of the insolation into electrical power that allows me to do almost SOTA local LLM stuff inside my house for free[1] that the parent commenter thought to be economically infeasible. Of course it's slow! So what! Right now I'm transcribing to text a podcast with whisper.cpp and it will take about as much time as the original podcast duration but I will be able to read it in 1/20th of the time.

Alternative interpretation of a downvote: we should all be enslaved to corporate electrical generation provided to "local" electric utility corporations so that we are economically incentivized to use cloud LLM providers. That's weird, no?

Teach me.

[1] It's a small nice house that cost ~$330K not too far off from my city center. This isn't rich privilege boasting.

downut··on GLM-5.2 – How to Run Locally
I have rooftop solar and I have been building credit with my electric utility even though the daily high temperature is well over 100F outside and a comfortable 75F inside. That includes running three AMD 12 thread 128GB systems with obsolete GPUs 24x7x365. I'm not a gamer, so 6 years ago I went low-end low-power GPUs. Boy am I dumb. Currently running the qwen3.6:27b, 35b, and gemma4:31b models just fine.

As soon as VRAM prices drop to sanity I'm going to load up and I could care less about the power draw.

Some parts of the future are absolutely great.

downut··on Mexican government unveils a prototype for a new homegrown, ultra-affordable EV
Have you ever paid attention to what's on the road in Mexico? I've driven there for 30 years and I've seen it all.

Then, there's the idea that Mexicans might not be able to manufacture a quality vehicle. My 2001 Toyota Tundra was manufactured in Mexico and I will drive it until I die. Basically a grail vehicle.

Places like Monterrey have multistory quite modern BYD dealerships. You might start shopping for monasteries ;-)

downut··on Mexican government unveils a prototype for a new homegrown, ultra-affordable EV
For the people who don't believe this, spend some time watching urban traffic in a place like Oaxaca. 4 is a bit of a stretch unless it's a couple of small kids (that happens) and the moto is not really a moped, but not much more powerful. There's occasional bulky cargo. I am also reminded of the multiple times we were riding in a bus in Cairo Egypt and passed a donkey cart in the left lane of a 6 lane-ish "free"way.

One of the first things I thought when I first saw this thing is, oh, there will be mods.

downut··on HP re-releases classic computer science calculator: The HP-16C
My wife and I were mid '80s chemical engineers. She liked her 15c, but I went on afterward into fundamental numerical analysis and was extremely happy with my 32S. I recently asked qwen3.6:35b|qwen3.6:27b|gemma4:31b (can't remember which one) all about the current state of replacement LR44 batteries for an "HP 32S Scientific Calculator". It was fucking adamant, aggressively so, that the calculator required 1 battery. LOL no, it sits before me and yes it needs 3. A 6 pack cost I dunno $6 off AMZ? Anyway I have now replaced the batteries in my daily tactile basic algebra calculator for the third time. If I don't have it in hand I use Free42. I... regret not remembering how to program these things, it was so intellectually elegant.

I logged on for the first time in a while to actually talk about nerd things. God I loved the 80s-2000.

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