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Comment: Fun, But Useless (Score 3, Funny) 66 66

This is a fun device that can show you what can be done with 3D printed plastic. That said, it's useless. It would be really cool if I could apply 1 pound of force to the crank, turn it a Million times, and have it apply a Million pounds of rotational force at the other end. But it's made of plastic, so it won't do that. Indeed, the fast-rotating parts would wear out before the slow-rotating part made a single turn. So it's not even good as a kind of clock.

All that said, it's a good conversation piece, and probably worth the price for that.

Comment: iOS users feel it (Score 1, Insightful) 310 310

I currently have a web radio transceiver front panel application that works on Linux, Windows, MacOS, Android, Amazon Kindle Fire, under Chrome, Firefox, or Opera. No porting, no software installation. See blog.algoram.com for details of what I'm writing.

The one unsupported popular platform? iOS, because Safari doesn't have the function used to acquire the microphone in the web audio API (and perhaps doesn't have other parts of that API), and Apple insists on handicapping other browsers by forcing them to use Apple's rendering engine.

I don't have any answer other than "don't buy iOS until they fix it".

Comment: Re:Kids don't understand sparse arrays (Score 1) 128 128

What happens to your 'standard' linked lists solution when you have ten values scattered over an array which is 1000! (factorial 1000) in each dimension? For most genuinely sparse arrays, a hashmap is a better approximation of an efficient implementation. Of course, there will be corner cases where you want to do something different, but linked lists strike me as an extremely poor solution except in arrays where more than about 10% of cells have data.

Comment: Re:TRWTF: List is used instead of Map (Score 1) 128 128

I should have read the linked questions before replying...

Stupid, stupid, STUPID! Why have numRows and numCols in a sparse array? Things with unnecessary, arbitrary bounds annoy me. My implementation of Conway's Game of Life runs on a sparse array precisely because that allows the world to stretch arbitrarily in any direction a glider goes, limited only by the capacity of the bignum library and the total store available to the program.

And this is how we teach computer science?

Sigh.

Comment: Re:TRWTF: List is used instead of Map (Score 1) 128 128

Sparse array entries, in general, are not necessarily immutable, although they may be so in this case. Most spreadsheets are implemented as sparse arrays, for example. But your point about the benefit of a map is well made.

Comment: Re:Randomness can't come from a computer program (Score 1) 64 64

Most of us do have a need to transmit messages privately. Do you not make any online purchases?

Yes, but those have to use public-key encryption. I am sure of my one-time-pad encryption because it's just exclusive-OR with the data, and I am sure that my diode noise is really random and there is no way for anyone else to predict or duplicate it. I can not extend the same degree of surety to public-key encryption. The software is complex, the math is hard to understand, and it all depends on the assumption that some algorithms are difficult to reverse - which might not be true.

Comment: Re:Bad RNG will make your crypto predictable (Score 2) 64 64

The problem with FM static is that you could start receiving a station, and if you don't happen to realize you are now getting low-entropy data, that's a problem.

There are many well-characterized forms of electronic noise: thermal noise, shot noise, avalanche noise, flicker noise, all of these are easy to produce with parts that cost a few dollars.

Comment: Randomness can't come from a computer program (Score 2, Interesting) 64 64

True randomness comes from quantum mechanical phenomena. Linux /dev/random is chaotic, yes, enough to seed a software "R"NG. But we can do better and devices to do so are cheap these days.

I wouldn't trust anything but diode noise for randomness. If I had a need to transmit messages privately, I'd only trust a one-time pad.

Comment: Re:I'm spending 60% of my monthly income on rent (Score 1) 939 939

Communism has been tried on a large scale - see Mao's Great Leap Forward.

Nope. That was a totalitarian socialist program pushing a collectivism that didn't work. Communism is a post-scarcity society and obviously scarcity was the thing Mao produced best.

Comment: Re:What's the score now? (Score 1) 77 77

I didn't actually work on GPUs very much at Pixar, the image computer I worked on was the grandfather of the SIMD image processing instructions on modern CPUs. What would become a GPU later on was a very expensive box from Silicon Graphics, I had one that cost at least a quarter Million dollars.

Comment: Re:What's the score now? (Score 5, Interesting) 77 77

If they actually told us how to program their microengines, something good might come of it. But they'll probably just BSD-license a list of numbers, as others have.

I liked writing bit-slice microcode at Pixar. I really could get every last bit of power out of the hardware.

Never try to teach a pig to sing. It wastes your time and annoys the pig. -- Lazarus Long, "Time Enough for Love"

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