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xaedes

1,010 karma · joined November 21, 2014

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xaedes··on Chatbots: Still dumb after all these years
Yes, "soft robotic grippers" can do it.
xaedes··on Archaeological dig reignites debate over the Old Testament’s historical accuracy
Here is something from Zoroastrianism akin to the Ark, connecting it with winter and "foul frost":

FARGARD II. Yima (gamshêd).

And Ahura Mazda spake unto Yima, saying: 'O fair Yima, son of Vîvanghat! Upon the material world the fatal winters are going to fall, that shall bring the fierce, foul frost; upon the material world the fatal winters are going to fall, that shall make snow-flakes fall thick, even an aredvî deep on the highest tops of mountains. And all the three sorts of beasts shall perish, those that live in the wilderness, and those that live on the tops of the mountains, and those that live in the bosom of the dale, under the shelter of stables. Before that winter, those fields would bear plenty of grass for cattle: now with floods that stream, with snows that melt, it will seem a happy land in the world, the land wherein footprints even of sheep may still be seen. Therefore make thee a Vara, long as a riding-ground on every side of the square , and thither bring the seeds of sheep and oxen, of men, of dogs, of birds, and of red blazing fires.

Therefore make thee a Vara, long as a riding-ground on every side of the square, to be an abode for men; a Vara, long. as a riding-ground on every side of the square, to be a fold for flocks. There thou shalt make waters flow in a bed a hâthra long; there thou shalt settle birds, by the ever-green banks that bear never-failing food. There thou shalt establish dwelling places, consisting of a house with a balcony, a courtyard, and a gallery. Thither thou shalt bring the seeds of men and women, of the greatest, best, and finest kinds on this earth; thither thou shalt bring the seeds of every kind of cattle, of the greatest, best, and finest kinds on this earth.

Thither thou shalt bring the seeds of every kind of tree, of the greatest, best, and finest kinds on this earth; thither thou shalt bring the seeds of every kind of fruit, the fullest of food and sweetest of odour. All those seeds shalt thou bring, two of ever, kind, to be kept inexhaustible there, so long as those men shall stay in the Vara. There shall be no humpbacked, none bulged forward there; no impotent, no lunatic; no poverty, no lying; no meanness, no jealousy; no decayed tooth, no leprous to be confined, nor any of the brands wherewith Angra Mainyu stamps the bodies of mortals. In the largest part of the place thou shalt make nine streets, six in the middle part, three in the smallest. To the streets of the largest part thou shalt bring a thousand seeds of men and women; to the streets of the middle part, six hundred; to the streets of the smallest part, three hundred. That Vara thou shalt seal up with the golden ring, and thou shalt make a door, and a window self-shining within.'

https://www.sacred-texts.com/zor/sbe04/sbe0408.htm

xaedes··on Group of monkeys kill over 250 dogs for 'revenge' in Indian town
Sounds pretty gruesome. However, the concept of it seems to be ancient. The great Indian epic of Ramayana has a part that tells how they build Adam's / Rama's bridge to Sri Lanka with the "help" of monkeys:

https://en.wikipedia.org/wiki/File:The_Monkeys_and_Bears_Bui...

xaedes··on How a Kalman filter works, in pictures
Welford's online algorithm for computing weighted mean is essentially just Kalman filtering: Weights are the inverse of measurement covariance, i.e. the information, the initial state is the first measurement, state transition and observation model are 1x1 identity matrices.
xaedes··on Why are German numbers backwards?
I often see a similar problem in code that deals with coordinate system transformations. But there is a simple solution! It boils down to properly naming your variables.

When using transformation matrices to transform from one coordinate system "In" into another coordinate system "Out" you have two options to name the matrix: M_{In,Out} or M_{Out,In}, which can be read as "In to Out" and "Out from In". Unfortunately what I often see is the first notation. It looks simpler at first, but it is actually backwards, similar to how the german numbers are backwards.

When you chain the transformations you get this weird forth and back:

M_{A to C} = M_{B to C} * M_{A to B}

M_{A,C} = M_{B,C} * M_{A,B}

Compare that to the (not backward) alternative:

M_{C from A} = M_{C from B} * M_{B from A}

M_{C,A} = M_{C,B} * M_{B,A}

Note how the Bs line up, C is the most left in both sides of the equation and A is on the right. When you transform a vector from coordinate system A to, lets say C, it looks like this: "vec_C = M_{C,A} * vec_A". Everything lines up and is in the natural order the transformations are taking place in. Compared to this, the backward notation is really confusing.

I see people make mistakes when dealing with transformation chains all the time because they use this weird M_{From,To} notation, or worse, no notation involving the coordinate systems at all.

Like take this example: "M = M1 * inv(M3) * M2", what does that even mean. Find names for the involved coordinate systems and name the transformations accordingly. That could be: M1 transforms to A from B, M3 is C_B, M2 is C_D. Then M is A_D:

B_C = inv(C_B)

A_D = A_B * B_C * C_D

xaedes··on Coconut: Simple, elegant, Pythonic functional programming
If you really need more than one line this will probably work:

  L |> map$(def (x) -> (
    y = 1/x;
    y*(1 - y)
  ))
You can also make multiline python lambdas by using brackets. That is if you can fit your code into an expression.
xaedes··on Autodiff from scratch
I recently came stumbled upon this autodiff in two dozen lines of python: https://github.com/breandan/picograd/blob/main/picograd.py
xaedes··on Are daily standups hurting your team?
Somehow these last two sentences seem to contradict each other.
xaedes··on Games that emphasize emergent narrative
This here is also a great game with emergent narrative: "One Hour One Life". Each time you only have one hour of lifetime and act in a evolving multiplayer world.

Just copy pasting the first comment on steam to show what kind of stories unfold:

I was born mere seconds before my twin sister in a once prosperous town. Through the years and hardships, the townsfolk seemed to be dwindling in numbers and there were not many left. My mother, Honey Nova was the leader of our people and a strong and kind woman. She took very good care of my sister and I. She named me Yun and my twin sister Yan. Life was easy as a child, I enjoyed playing outside with my twin in the berry fields and following my mother as she worked as a gravekeeper. She was a hard working woman and was very close with her two brothers. When it came time for her to pass on, she begged to be buried next to them.

My sister and I gathered around her as she stood on her gravesite (she always put her work first, a dedicated grave keeper). We cried as we said our last goodbyes - her dying words were "I'm proud of you daughters". We took off our hats in respect and steeled our resolve to become the village's next gravekeepers. Our first order of action was to bury our mother and uncles and then to find them gravestones.

Our work was busy and fast-paced. We scoured the wilderness for headstones, built paths and plots, and even found a few wayward relatives in the wilderness that could finally be put to rest. A few years after my mother died I had my very first son. Stillborn. Too young for a grave, too old for the pain it left in my heart. I never even gave him a name. I was eventually able to conceive another son, I named him Yama. He was a quiet child, never speaking much - but seemed to intrinsically understand the world. He immediately set out and fed himself and started working. I was so proud! He was a role model for his (many) cousins. My sister was a fertile woman.

Then along came my second son... I gave him the name Yurem.

Yurem was a little more, spirited. Around the age of four is when I noticed he wasn't quite right. I retired from my job to stay home with him and hopefully instill some of my mother's values - love, respect, strength. Around the age of 14 he started acting out in the kitchen and I grew increasingly concerned. He would throw off his clothes and hide in the corner mumbling things about God and witches. I pleaded with him to put his pants back on, nothing seemed to get through to him and nothing could prepare me for the horrors about to unfold.

In the following year, Yurem snapped. He had found the body of my first born son and approached me. He screamed at me, veins popping from his neck and forehead. He said I was a witch, that I had an abortion and that I needed to be cleansed. My oldest son Yama overheard and came to my defense. It was then that we saw the knife behind Yurem's back. Yama dove in front of me, telling his brother that I wasn't a bad person. That stillborn children happen all the time. We don't have hospitals. But there was no talking Yurem down, he had finally jumped head first into the deep end. As Yurem lunged for me, Yama grabbed him and wrested him to the ground. After a long tense struggle, he finally managed to wrench the knife from Yurem's hands, but suffered several wounds in the process. Struggling for his breath, he raised the bloody knife back towards Yurem and said he will die for his actions. Yurem slunk to the ground and began sobbing hysterically.

About this time, other members of the village were alerted to the unfolding scene and rushed to the room. When they entered, all they saw was Yurem crying in a heap on the floor and Yama with a bloodied knife. I tried to explain the situation, but things started happening so fast. The leader called for the exile of Yama and all of the villagers immediately followed suit. They cursed him! The poor child that only ever tried to protect his mother. The one that held so much promise. His body turned to bones almost in an instant, unable to carry the weight of all the curses. I stared, unable to speak, at the skull of my child. All I could pictures was his bright brown eyes as he looked up at me when he was a boy.

The villagers slowly filtered out of the room one by one. It was when the last one left that I heard it, a slow, menacing chuckle. Yurem was staring at me from across the room. I screamed for help and ran out of the room. I told everyone who would listen the story of what actually happened, but nobody would listen. Yurem disappeared at some point, maybe into the wilderness, maybe into the delivery truck that frequented our village. I lived the rest of my life in fear, hoping he would never return. The only respite was the love of my gentle sister and my many nieces. As our lives neared their end, my twin sister and I made our way to our graves. Her children came one by one to tell her they loved her. I stood alone, with only one random villager running by that said RIP to me. My sister died shortly before me and I could feel death's fingers enclosing. My last words were: Curse Yurem Nova.

xaedes··on Why doesn’t natural immunity count in the US?
With all due respect, I rather think the virus is the cause.
xaedes··on Our fridge just emailed us to say we opened its door too many times
In Battlestar Galactica humanity's last defense was this big "dumb" battlestar spaceship with sparsly connected systems.

Sometimes it feels like the internet (of things) is the breeding ground of the Cylons in our world.

xaedes··on Chekhov's Gun
"The Room", by Tommy Wiseau, is a movie where Chekhov's gun isn't applied. It contains lots of small happenings with no further relevance. It has lots of other issues, technically speaken.

But together they make this film not only amateurish, but it also gives it a certain kind of realism. In real life stuff happens and still may have no further relevance to the "story" after all. In real life there is nobody enforcing Chekhov's gun.

Together with the other charming mistakes and bad acting the film feels quite authentic. It gives this impression that someone just wanted to tell his story, despite not being as professional as we are used to. Like a little child coming home from playing in the woods that excitetly blabbers out the story of what he just experienced.

xaedes··on Extreme Ironing
But then is 'silly' translatable into any other language at all? With all its exact meanings, and nothing more?
xaedes··on Show HN: I made a meme creator that makes around $4k a month
> When it's a subscription as a customer you have more trust that it will continue working. When it's a one time purchase, who knows how long it will last.

Funny, for me this is the total opposite: subscription software may end any time and then you got nothing. One time purchased software you can just continue to use. Well, I guess in the games of rent-seeking, cloud-only, security and updates the viability of this is fading...

xaedes··on Rain falls at the summit of Greenland Ice Sheet for first time on record
> This year has seen both a high melt as well as a high accumulation of snow, the balance of which currently lies clearly at the positive end - Greenland has far more accumulated snow than average.

Seems to apply for the whole northern hemisphere. Look at the diagrams for 'the current Northern Hemisphere snow water equivalent relative to the long-term mean and variability' (GCW/FMI SWE Tracker) at https://globalcryospherewatch.org/state_of_cryo/snow/

Last year this diagram was similar.

xaedes··on Show HN: I built an AI art installation at home generating new pieces on the fly
I think the generated pixels are not the art. The whole piece is the art, made by the artist, i.e. the OP.
xaedes··on A wind-powered vehicle that can travel twice as fast as the wind itself
"The physics of a push-me pull-you boat"

http://202.38.64.11/~cxyu/AJP_pushmepullyouboat.pdf

xaedes··on Sea monsters and their inspiration: serpents, mermaids, the kraken and more
They should have mentioned the Beluga. Their body can deceptively look like humans in tight whole body suits. Just look for images "beluga mermaid".
xaedes··on A wind-powered vehicle that can travel twice as fast as the wind itself
$10.000 got donated and a lot of publicity created. I think it is just good marketing. Dunno if it is worth 10k but it got on HN a few times, so it undoubtedly works. And the topic itself is super interesting!
xaedes··on A wind-powered vehicle that can travel twice as fast as the wind itself
This is similar to flying in air.

I suppose when your craft is big (or long) enough you could leverage differences in luminous flux (or intensity?) to generate some thrust. The differences will be tiny and the necessary craft size big. One would have to run the actual numbers, but it _could_ work in principle.

Compressing air by moving through it to leverage the resulting difference in velocities sadly won't work =( The steady state is then just the speed of air. I guess for light this also applies in a similar way.

xaedes··on Captcha pictures force you to look at the world the way an AI does
I think it is best to click the tile even if it only has a small part of the "object" in it. Other instances may have the same image but the grid is offset by a few pixels. At one point the tile does not contain the object at all and won't get any clicks. That way they could determine boundaries with higher resolution than the grid cell size.
xaedes··on Lisp in an “impossible” language, the most complex Malbolge program to date
If you are into this you might want to check out the Wizardry book series by Rick Cook:

"It all began when the wizards of the White League were under attack by their opponents of the Black League and one of their most powerful members cast a spell to bring forth a mighty wizard to aid their cause. What the spell delivered was master hacker Walter "Wiz" Zumwalt. The wizard who cast the spell was dead and nobody— not the elves, not the dwarves, not even the dragons—could figure out what the shanghaied computer nerd was good for.

But spells are a lot like computer programs, and, in spite of the Wiz's unprepossessing appearance, he was going to defeat the all-powerful Black League, win the love of a beautiful red-haired witch, and prove that when it comes to spells and sorcery, nobody but nobody can beat a Silicon Valley computer geek!"

xaedes··on YouTuber Wins Crazy $10k Bet with Professor by 'Breaking' the Laws of Physics
I suspect it was an organized publicity stunt. In the interview the Prof. said "now here is the real danger, because if Derek drives very close to the wind that difference in speed goes to zero. if it's one millionth of one percent, that's like a nuclear bomb exploding behind him.", refering to a formula where the force is calculated with speed difference in denominator.

Obviously he can't be serious about it, because it is inconsistent with the belief that the car can't go faster than wind.

Anyway, the whole thing was very interesting and educational.

xaedes··on YouTuber Wins Crazy $10k Bet with Professor by 'Breaking' the Laws of Physics
> Or, does this vehicle, after acceleration has completed, purport to continuously travel faster than the wind at an indefinite steady state?

Yes. The vehicle can go faster than the wind in steady state condition. Depending on efficiencies 'any' velocity is possible. It creates thrust by leveraging the different speeds of two media (air and ground). Also works as a boat with two propellers.

xaedes··on Man dies of a heart attack after minors swatted him over his rare Twitter handle
Why send the officers at all and risk their lifes, can't we just install weapons on the drones? Oh yea we probably can. dramatic evil music starts
xaedes··on Component Graph System (2017)
There is EnTT, an ECS as C++ library:

EnTT is a header-only, tiny and easy to use library for game programming and much more written in modern C++. Among others, it's used in Minecraft by Mojang, ...

https://github.com/skypjack/entt

xaedes··on Are animals more conscious than we are?
I think this text is very relevant:

BEFORE THE SOUL DAWN by Helen Keller

Before my teacher came to me, I did not know that I am. I lived in a world that was a no-world. I cannot hope to describe adequately that unconscious, yet conscious time of nothingness. I did not know that I knew aught, or that I lived or acted or desired. I had neither will nor intellect. I was carried along to objects and acts by a certain blind natural impetus. I had a mind which caused me to feel anger, satisfaction, desire. These two facts led those about me to suppose that[142] I willed and thought. I can remember all this, not because I knew that it was so, but because I have tactual memory. It enables me to remember that I never contracted my forehead in the act of thinking. I never viewed anything beforehand or chose it. I also recall tactually the fact that never in a start of the body or a heart-beat did I feel that I loved or cared for anything. My inner life, then, was a blank without past, present, or future, without hope or anticipation, without wonder or joy or faith.

It was not night—it was not day. . . . . . But vacancy absorbing space, And fixedness, without a place; There were no stars—no earth—no time— No check—no change—no good—no crime. [143]

My dormant being had no idea of God or immortality, no fear of death.

I remember, also through touch, that I had a power of association. I felt tactual jars like the stamp of a foot, the opening of a window or its closing, the slam of a door. After repeatedly smelling rain and feeling the discomfort of wetness, I acted like those about me: I ran to shut the window. But that was not thought in any sense. It was the same kind of association that makes animals take shelter from the rain. From the same instinct of aping others, I folded the clothes that came from the laundry, and put mine away, fed the turkeys, sewed bead-eyes on my doll's face, and did many other things of which I have the tactual remembrance. When I wanted anything I liked,—ice-cream,[144] for instance, of which I was very fond,—I had a delicious taste on my tongue (which, by the way, I never have now), and in my hand I felt the turning of the freezer. I made the sign, and my mother knew I wanted ice-cream. I "thought" and desired in my fingers. If I had made a man, I should certainly have put the brain and soul in his finger-tips. From reminiscences like these I conclude that it is the opening of the two faculties, freedom of will, or choice, and rationality, or the power of thinking from one thing to another, which makes it possible to come into being first as a child, afterwards as a man.

Since I had no power of thought, I did not compare one mental state with another. So I was not conscious of any change or process going on in my brain[145] when my teacher began to instruct me. I merely felt keen delight in obtaining more easily what I wanted by means of the finger motions she taught me. I thought only of objects, and only objects I wanted. It was the turning of the freezer on a larger scale. When I learned the meaning of "I" and "me" and found that I was something, I began to think. Then consciousness first existed for me. Thus it was not the sense of touch that brought me knowledge. It was the awakening of my soul that first rendered my senses their value, their cognizance of objects, names, qualities, and properties. Thought made me conscious of love, joy, and all the emotions. I was eager to know, then to understand, afterward to reflect on what I knew and understood,[146] and the blind impetus, which had before driven me hither and thither at the dictates of my sensations, vanished forever.

[...]

https://www.gutenberg.org/files/27683/27683-h/27683-h.htm

xaedes··on Programmers, teach non-geeks the true cost of interruptions (2014)
That sounds like this line of thinking:

If you had to use a piece of software that ran lengthy operations and you had to wait very long for the results, would it be more effective to wait for the results or fix the program so it runs faster?

I.e. Some feature needs too long to be implemented? Ok lets fix these slow workers, send all the devs to a workshop for time-management and speed-coding or whatever.

xaedes··on Manual for a popular facial recognition tool shows how much the software tracks
Why do we need facial recognition everywhere? We don't. Can we just stop building a sci-fi dystopian society?
xaedes··on A woman's battle to prove she isn't dead
This reminds me of "The Machine Fired Me - No human could do a thing about it!" [1], where a guy got fired by some bug in the system and no one could stop or reverse it. It was posted on HN [2] three years agos.

[1] https://idiallo.com/blog/when-a-machine-fired-me

[2] https://news.ycombinator.com/item?id=17350645

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