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apart from blind users, who are also now completely unable to use their screenreaders with your site


aria-hidden="true" should take care of that.


my thoughts exactly - crazy to know all these arcane SIMD opcodes but not know basic maths!!


Square root computation can be tricky, often relying on approximations. These approximations tend to perform best for mid-range values, while accuracy can degrade for very large or very small values. With this in mind, a product of roots is generally more accurate than a root of products.

From a SIMD perspective, it’s worth noting that on most platforms, the cost of computing one square root or two is the same. On modern x86 server CPUs, for instance, you can calculate up to 8 double-precision roots in parallel with identical latency. So there’s no additional cost in terms of performance.

I hope this sheds some light on the design of my code.

PS: In a previous life, I did research in Astro- and Plasma Physics. While I don’t claim to remember all the Math, it’s usually more productive to ask for clarification than to assume ignorance ;)


> it’s usually more productive to ask for clarification than to assume ignorance ;)

Good reminder for me and anyone else right there, nicely put.


Moments like that are enlightening. When you see something really improbable (knowing advanced SIMD while appearing to ignore basic algebra), it's likely the moment you see a gap in your picture of the world. So it's tine to learn something new and likely unexpected (else you could have guessed).


So the butterflies flew 2600 miles only to be killed for study by some curious entomologists?


An old BASIC program, with full explanation


Looks dead. No release for +3 years


it's alive, last commit 18 days ago https://github.com/davidedc/Fizzygum/commits/master


aka Sinclair ZX81. There was such a program in Your Computer that would toggle between fast and slow mode to generate tones. It was a actually a trivial 8 or 16 step tracker, so you could even make beats...

And here's the program listing!

https://archive.org/details/your-computer-magazine-1982-03/p...


OneTick, Kx, and QuasarDB


Thanks!


Paper doesn't address what measures the aliens might use to disguise any obvious signature of the starshade.

You'd think that the aliens might not be too keen to create huge beacon advertising their presence to all and sundry...


One cannot assume that an alien can think in a fashion similar to Earth animals.

Humans have the ability to imagine a possibility for which no supporting evidence currently exists--that species alien to our solar system might exist. That ability might not be shared by the species we can imagine. That is, humans can imagine a species that cannot imagine humans. Such aliens would not even realize that building a planet-sized object that cannot be explained by natural processes might present an existential risk.

We, of course, are afraid of hypervelocity impact weaponry, even while having no evidence whatsoever that any such weapon exists anywhere in the universe.

Of course, that just means that any species that did fear annihilation by near-c rocks smashing into their planet would simply disguise their star shade so well that we could not detect it. Meaning that any solar shade we can detect was not likely built by any species able to think like us.

We could clean up by selling them insurance.


I'm not sure how you propose a species that can't imagine things that don't exist would advance technologically to space travel.


Investigation of serendipitous results.


They may not need imagination if they can build dyson spheres, new telescopes could help verify where we should put our efforts at contact: http://www.sciencealert.com/researchers-just-found-a-second-...


There is no stealth in space.

Therefore, instead of hiding, the aliens are going to pro-actively fry every competitor civilization by using their solar shades as a Nicoll Dyson Beam... :-)

https://www.youtube.com/watch?v=RjtFnWh53z0


Best disguise would be reduced solare output or another inner sync planet giving partial shade..


Using a yellow whiteboard marker, simply colour in the LED's face. Problem solved.


  perl -E 'sub x{say;for(<$_/*>){&x;unlink}};x for@ARGV' *

  perl -E 'push@ARGV,<$_/*>for@ARGV;say,unlink for@ARGV' *


Isn't that just "rm -rv *"? The original spec was to only delete files, not directories - and only those matching a given pattern, at that.

Also, I think yours would go into an infinite spin if it met a symlink loop (say, "ln -s . foo") - File::Find is hardened against that kinda shenanigans.


fair. not quite so pretty now...

  perl -E 'for(@ARGV){say,unlink for<$_/whatever*>;push@ARGV,($_)x(-d^-l)for<$_/*>}' .


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