I don't know what the original poster meant, but it is common to refer to the bit depth as an extra "dimension" in an image, because it can carry information just like the two spatial dimensions can.
So, a 1x1x1 image might be referring to a single pixel which can be either black or white:-)
Uhm.. No, use GIF. Using PNGs is stupid unless twhen done for no good reason.
This is the stupidest comment I've read here. PNG and GIF are quite similar, oh, except that PNG supports 1, 2, 4, 8, and 16 bit color in each channel, it supports 1, 2, 4, 8, or 16 bit alpha channel, it has native grayscale, indexed, and truecolor modes, it has an array of predictive filters which enhance the compression ratio, it has support for display device gamma correction, and it uses an unpatented compression scheme. Contrast this with GIF which only supports 8 bit indexed mode, no predictive filtering, no gamma, with a patent-encumbered compression scheme. (Yes, the patent is expired. People still won't touch the fucker with a ten foot pole).
I rebut your comment by saying, "Why the HELL would anyone use a GIF?"
Web site accessibility (use image type supported by all major browsers)
Have you even checked in the last, say, 3 years? Everybody supports PNG. The IE implementation used to have (still has?) problems with the alpha channel, but so what?!
Bandwidth conservation
PNGs tend to be smaller than their GIF counterparts. Either you have no experience (in which case you shouldn't be commenting), or you don't know how to select an appropriate color mode for the PNGs to maximize the compression.
I have a hunch that you think PNG is a lossy format. You're ignorant.
The old-school trick is to back up the file system to tape, reformat the disk and do a restore.
These days you could just use a second disk. It would be faster, too.
I wonder if there's some way for a RAID to constantly, dynamically optimize itself. After all, it's striped and redundant, there must be all kinds of funky tricks you can play to reorganize data on the fly...
Dirac (pronounced Dih-RAK) was a physicist and mathematician. His name appears in this context because of the "Dirac delta function," otherwise known as an impulse function. It lies at the heart of linear signal theory, including wavelet theory.
The first amendment ONLY RESTRICTS THE FEDERAL GOVERNMENT (actually just Congress...), as do all the amendments.
Who other than the government can censor? How can a private individual or organization censor another? You might tape my mouth shut, but that would be assault. You could kill me, but that would be murder. You can threaten me, but that would be blackmail. You can accuse me of slander, but that would be false. You can accuse me of copyright infringement, but there's nothing copyrightable here.
You can make me enter into a contract, and that's the only recourse you have. But if I'm under 18, it's not enforceable.
Must be nice being as young, stupid, and naive as you seem in your post.
It must suck being a crotchety old buzzard who sits around all day flapping his lips off at anyone who (shock!) has a sense of ideals. You see opinions you don't understand and assume they must be born of ignorance, when the real fact is you're too lazy to do the half minute's worth of thinking required to see the logic behind them.
The colleges are depending on the testing companies maintaining a high correlation between the scores and college performance.
And they are quite stupid for doing so, exactly for the reasons we're discussing here. The test can be manipulated and people can cheat. Relying on the scores is ludicrous. Such tests are pointless. Threatening legal action against students who talk about the answers is hilarious and demonstrates both the supreme delusion of the College Board and their terrible callousness.
Oh, wait a minute, you must be a college student that cheats, ignores instructions, and breaks the rules. Nevermind.
You are a fool to think that because one man defends another, he therefore agrees with all the opinions of that other. And your ad hominem attack is not only baseless, it's childish and logically impotent. Making personal characterizations over the Internet is quite dangerous and more than likely to make you look like an idiot.
It's possible for a student to come out of a CompSci course and be unable to explain why a containment-based widget toolkit is better than a positional one, yet can talk about VM swapping algorithms and implementing the fastest hashtable probing all day. Which would you rather employ?
The one who understands the difference between computer science and software engineering?
Would you hire a physicist to design a bridge? It would be insane.
Quit bitching about CS and go to the field you should be studying: engineering. Any kind of engineering. Good engineering practices are the same across the different types of engineering. But to expect computer science students to learn these practices is ludicrous. That isn't the point of CS, it shouldn't be the point, and I hope to God it never becomes the point.
Multiple choice questions are resued so that the College Board can compare how well people did year-to-year.
Which is a pointless endeavor, since people will share the test answers. Ever notice what happened the last time you told a teenager not to do something? Did they do what you told them? Wake up, man. Sitting around "hoping" that the kids won't talk is fucking delusional.
The playing field should be level.
Wow. If they manage to pull off a "level" playing field, they'll be the first to ever do so with a test like this. Face it, all tests are biased, and having students discussing the answers is just another form of bias. You plan for this, and deal with it.
Students who tried to cheat this way HAVE had legal action persued against them
First, if you consider the free discussion of test questions among students outside of the test-taking environment to be cheating, you have a truly draconian take on things. Second, unless the kids signed some kind of legally binding NDA, there is no law which could allow the College Board to prosecute them for any offense at all -- haven't you heard of the fucking First Amendment? Copyright can't stop them, since it is a fact that the answer to question #115 is letter D, and you cannot copyright a fact. And aren't some of these kids under 18 anyway? An NDA can't apply to them, since any contract they enter into is null and void.
Basically the only recourse they have again people discussing the test is arbitrarily making their score zero. This is stupid, it denies reality, and is generally evil.
What's the mathematical equivalent of a for-loop? memcpy? class?
How ridiculously narrow your thinking is... There are plenty of very powerful languages that have no concept of loops, or direct memory access. And if you think the idea of a "class" has no mathematical equivalent you are really quite ignorant.
I won't even get into databases, disk latency, networking, or dynamic libraries.
Programming doesn't have anything intrinsically to do with any of that. It is, quite rightly, hidden away from the typical user, and a programmer is a user too. Not all programmers are wizards who understand the inner workings of everything the machine does. They do not need to be. They should not need to be.
I'll admit that people with no formal programming training are sometimes very idiosyncratic in their programming styles. Sometimes they don't understand the concept of commenting code. But the code they write is no better or worse, from the standpoint of utility and efficiency, than the code a "professional" programmer might produce.
An intelligent person is usually able to apply that intelligence across a wide range of applications, in spite of a lack of formal training. Haven't you noticed that yet?
Why do you say "virtual?" The antenna is just as real as a metal wire, the only difference is that the positive charges in a plasma are free to move, whereas in a metal the positive charges are locked in the lattice.
Just because it's not a solid doesn't make it spooky or virtual...
virtual radio telescopes could be of practically unlimited size, by this arrangement.
Not really, since the plasma has to be kept "hot" and at low pressures in order to prevent it from recombining back into "normal" uncharged matter again. A device capable of maintaining such a large plasma would require enormous amounts of power and maintainence.
A 500 volt battery with a low impedance will kill you instantly. You are right that it is the current which kills, but it is the voltage which causes the current.
Your electric fence can't deliver a lethal shock because the circuit is formed through the earth (soil). The soil has a high impedance, so very little current flows even across 10000 volts. The fence initially delivers a very strong shock because your body acts like a capacitor charging up. Once you are "charged" (i.e., at a high voltage) the current only trickles through because the soil has such a high resistance.
A 12 volt car battery is capable of delivering thousands of amps if it is shorted through a small resistance. Hypothetically, if you took a steel wrench and shorted the contacts, the wrench would melt from the huge current. However, 12 volts is not enough to penetrate your skin, so if you grasp the battery terminals with your hands nothing will happen.
There's no simple rule such as "Only the current kills." The short answer is that unless you really have a good idea of how electricity actually works, you are better off staying away from anything that says "high voltage" or "high current." Electricity can behave in ways that are hard to predict, even for people experienced in handling it. It behaves according to laws, but there can always be something you hadn't thought of.
[...] append information to some kind of shared memory block [...]
Which also requires serialization and does not solve the problem whatsoever. It does, however, cause your locking to become more fine-grained leading to a smaller probability of serialization induced Heisenbug-ism.
Do you really want to debug using a technique that only usually works, and the rest of the time simply masks the problems?
My rule of thumb is, if you produce more than 1 synchronization bug per ten thousand lines of code, you don't understand multithreaded programming correctly, and somebody should take the samurai sword away. You'll hurt someone with that.
If you want the line buffered behavior even when outputting to non-terminal devices, without having to explicitly call fflush() after every line, you can force the stdout stream into line buffered mode like this:
setvbuf(stdout, NULL, _IOLBF, 0);
You must do this before you use stdout in any way.
The electricity that powers this best still comes from the same pollution belching power plant as other refridgerators.
Pollution belching? Coal and oil fired plants haven't released nasty black smoke full of sulfur gases for years. Pretty much the only "bad stuff" coming out of modern petrochemical plants is CO2. Bad for the environment, yes, but I hardly think it qualifies as "pollution belching."
Do you really think people still tolerate smokestacks blasting thick, black, pungent smoke into the atmosphere? Have you ever seen a coal-fired plant?
The other major environmental impact is heat. Coal plants use river water to transfer the heat energy in their turbines. They then reject the heated water back into the river again, wreaking havoc on local ecosystems. Nuclear plants have this same problem. The only thing that sets nuclear above coal is the fact that it releases no CO2.
Having said that, I agree with you that nuclear is what we should be heading toward, at least in the interim until we figure out what the hell the real solution is.
Christians are promised an enternal life in Heaven. We are not promised omniscience or omnipotence.
How can eternal life be consistent with the second law of thermodynamics? All things tend toward disorder -- to create order requires energy, and an increase in entropy which outmatches the decrease in some localized area. Hence God must have an infinite supply of energy in order to give you eternal life. Where does this energy come from?
They make a bold statement in the first sentence about consciousness
Since when is it bold to argue from the hypothetical? People do this all the time. Nobody stated that consciousness is a form of computation. Read what the hell he said: "In this case, if one treats consciousness, conservatively, as merely a form of computation [...]"
I'd say the paragraph you quote is mostly "filler" because it presents an argument based on an unproven assumption, but that alone doesn't make it unscientific. The guy is raising an interesting idea, nothing more.
For centuries, scientists have written things like this: "If in the future we discover that X is true, then we will know that Y and Z are also true." This statement is valuable in several ways. If we find that X is true, then we immediately know Y and Z. We don't have to wait until we know X in order to work out the logic. Furthermore, if we somehow discover that Y and Z are NOT both true, then we immediately know that X cannot be true (the law of contrapositives).
So his statement is actually quite valuable. If we discover that "consciousness is infinite" (whatever that means) then we will immediately know that it must not be based on computation. If you can't see the value in that, it's only because you're stupid.
This is not science, it's a cry for attention.
You're trying to look smart. You're failing quite miserably.
This computer MUST simulate the actions of this mass at the same speed or slower than the actions it's actually trying to simulate.
Interesting idea. If the computer could simulate reality faster than reality itself unfolds, then you could use the computer to simulate itself at a faster rate than it can itself execute. And of course, this simulated super-fast computer could also simulate an even faster version of itself, etc etc. There would be no bound to how fast such a machine could compute. This is in direct violation of the results put forth in this paper.
Therefore I think we can confidently state the following:
Any computer capable of simulating a Turing-complete computational device is restricted to simulations which run slower than the machine itself can execute. You can't use a computer to simulate a faster computer. This might seem intuitively obvious, but now we have a proof of it.
Hold on right there. What have they infringed upon?
What they've done is very low and dishonest, but I highly doubt they've broken any laws or infringed on anything. I can't imagine that there is a law saying that one piece of software cannot "lie" to another -- was the kernel module Under Oath or something? (And if there was such a law, it would be a truly dangerous and stupid law.)
Why on earth is the code written such that a \0 will break it?
Because that's how C handles strings. A string is a series of non-zero bytes terminated by a zero byte.
So the short answer to your question is that the code is written in that way because it has been Ordained By God (i.e., the ISO C standards committee).
Interestingly, and had you read the article links you would have known this, Linus suggests working around this "trick" by making the license strings into Pascal-style strings where the string length is explicitly indicated by a prefix word. Doing so would cause that string to become incompatible with all other string manipulation functions so it is not something which is done lightly, or on a whim.
Slashdot Mirror
I don't know what the original poster meant, but it is common to refer to the bit depth as an extra "dimension" in an image, because it can carry information just like the two spatial dimensions can.
So, a 1x1x1 image might be referring to a single pixel which can be either black or white :-)
This is the stupidest comment I've read here. PNG and GIF are quite similar, oh, except that PNG supports 1, 2, 4, 8, and 16 bit color in each channel, it supports 1, 2, 4, 8, or 16 bit alpha channel, it has native grayscale, indexed, and truecolor modes, it has an array of predictive filters which enhance the compression ratio, it has support for display device gamma correction, and it uses an unpatented compression scheme. Contrast this with GIF which only supports 8 bit indexed mode, no predictive filtering, no gamma, with a patent-encumbered compression scheme. (Yes, the patent is expired. People still won't touch the fucker with a ten foot pole).
I rebut your comment by saying, "Why the HELL would anyone use a GIF?"
Web site accessibility (use image type supported by all major browsers)
Have you even checked in the last, say, 3 years? Everybody supports PNG. The IE implementation used to have (still has?) problems with the alpha channel, but so what?!
Bandwidth conservation
PNGs tend to be smaller than their GIF counterparts. Either you have no experience (in which case you shouldn't be commenting), or you don't know how to select an appropriate color mode for the PNGs to maximize the compression.
I have a hunch that you think PNG is a lossy format. You're ignorant.
If only we could get the American education system to understand this concept...
These days you could just use a second disk. It would be faster, too.
I wonder if there's some way for a RAID to constantly, dynamically optimize itself. After all, it's striped and redundant, there must be all kinds of funky tricks you can play to reorganize data on the fly...
Well you can't be too careful when you're dealing with Slashdotters with UID > 700000...
Dirac (pronounced Dih-RAK) was a physicist and mathematician. His name appears in this context because of the "Dirac delta function," otherwise known as an impulse function. It lies at the heart of linear signal theory, including wavelet theory.
Who other than the government can censor? How can a private individual or organization censor another? You might tape my mouth shut, but that would be assault. You could kill me, but that would be murder. You can threaten me, but that would be blackmail. You can accuse me of slander, but that would be false. You can accuse me of copyright infringement, but there's nothing copyrightable here.
You can make me enter into a contract, and that's the only recourse you have. But if I'm under 18, it's not enforceable.
Must be nice being as young, stupid, and naive as you seem in your post.
It must suck being a crotchety old buzzard who sits around all day flapping his lips off at anyone who (shock!) has a sense of ideals. You see opinions you don't understand and assume they must be born of ignorance, when the real fact is you're too lazy to do the half minute's worth of thinking required to see the logic behind them.
The colleges are depending on the testing companies maintaining a high correlation between the scores and college performance.
And they are quite stupid for doing so, exactly for the reasons we're discussing here. The test can be manipulated and people can cheat. Relying on the scores is ludicrous. Such tests are pointless. Threatening legal action against students who talk about the answers is hilarious and demonstrates both the supreme delusion of the College Board and their terrible callousness.
Oh, wait a minute, you must be a college student that cheats, ignores instructions, and breaks the rules. Nevermind.
You are a fool to think that because one man defends another, he therefore agrees with all the opinions of that other. And your ad hominem attack is not only baseless, it's childish and logically impotent. Making personal characterizations over the Internet is quite dangerous and more than likely to make you look like an idiot.
The one who understands the difference between computer science and software engineering?
Would you hire a physicist to design a bridge? It would be insane.
Quit bitching about CS and go to the field you should be studying: engineering. Any kind of engineering. Good engineering practices are the same across the different types of engineering. But to expect computer science students to learn these practices is ludicrous. That isn't the point of CS, it shouldn't be the point, and I hope to God it never becomes the point.
Which is a pointless endeavor, since people will share the test answers. Ever notice what happened the last time you told a teenager not to do something? Did they do what you told them? Wake up, man. Sitting around "hoping" that the kids won't talk is fucking delusional.
The playing field should be level.
Wow. If they manage to pull off a "level" playing field, they'll be the first to ever do so with a test like this. Face it, all tests are biased, and having students discussing the answers is just another form of bias. You plan for this, and deal with it.
Students who tried to cheat this way HAVE had legal action persued against them
First, if you consider the free discussion of test questions among students outside of the test-taking environment to be cheating, you have a truly draconian take on things. Second, unless the kids signed some kind of legally binding NDA, there is no law which could allow the College Board to prosecute them for any offense at all -- haven't you heard of the fucking First Amendment? Copyright can't stop them, since it is a fact that the answer to question #115 is letter D, and you cannot copyright a fact. And aren't some of these kids under 18 anyway? An NDA can't apply to them, since any contract they enter into is null and void.
Basically the only recourse they have again people discussing the test is arbitrarily making their score zero. This is stupid, it denies reality, and is generally evil.
How ridiculously narrow your thinking is... There are plenty of very powerful languages that have no concept of loops, or direct memory access. And if you think the idea of a "class" has no mathematical equivalent you are really quite ignorant.
I won't even get into databases, disk latency, networking, or dynamic libraries.
Programming doesn't have anything intrinsically to do with any of that. It is, quite rightly, hidden away from the typical user, and a programmer is a user too. Not all programmers are wizards who understand the inner workings of everything the machine does. They do not need to be. They should not need to be.
I'll admit that people with no formal programming training are sometimes very idiosyncratic in their programming styles. Sometimes they don't understand the concept of commenting code. But the code they write is no better or worse, from the standpoint of utility and efficiency, than the code a "professional" programmer might produce.
An intelligent person is usually able to apply that intelligence across a wide range of applications, in spite of a lack of formal training. Haven't you noticed that yet?
Spatial security == the beam goes where you want, as opposed to all over the place.
Spectral security == the edges of the beam spectrum are very well defined, with very little "spill" into neighboring frequencies.
Just because it's not a solid doesn't make it spooky or virtual...
virtual radio telescopes could be of practically unlimited size, by this arrangement.
Not really, since the plasma has to be kept "hot" and at low pressures in order to prevent it from recombining back into "normal" uncharged matter again. A device capable of maintaining such a large plasma would require enormous amounts of power and maintainence.
But water doesn't conduct. It is the ions in the water (i.e., the compounds which make up human urine) which conduct.
Pure, distilled water is a very good insulator. The problem is keeping the impurities out, which is quite hard.
Your electric fence can't deliver a lethal shock because the circuit is formed through the earth (soil). The soil has a high impedance, so very little current flows even across 10000 volts. The fence initially delivers a very strong shock because your body acts like a capacitor charging up. Once you are "charged" (i.e., at a high voltage) the current only trickles through because the soil has such a high resistance.
A 12 volt car battery is capable of delivering thousands of amps if it is shorted through a small resistance. Hypothetically, if you took a steel wrench and shorted the contacts, the wrench would melt from the huge current. However, 12 volts is not enough to penetrate your skin, so if you grasp the battery terminals with your hands nothing will happen.
There's no simple rule such as "Only the current kills." The short answer is that unless you really have a good idea of how electricity actually works, you are better off staying away from anything that says "high voltage" or "high current." Electricity can behave in ways that are hard to predict, even for people experienced in handling it. It behaves according to laws, but there can always be something you hadn't thought of.
Which also requires serialization and does not solve the problem whatsoever. It does, however, cause your locking to become more fine-grained leading to a smaller probability of serialization induced Heisenbug-ism.
Do you really want to debug using a technique that only usually works, and the rest of the time simply masks the problems?
My rule of thumb is, if you produce more than 1 synchronization bug per ten thousand lines of code, you don't understand multithreaded programming correctly, and somebody should take the samurai sword away. You'll hurt someone with that.
You should call it the 10nd edition. It confuses people better that way.
setvbuf(stdout, NULL, _IOLBF, 0);
You must do this before you use stdout in any way.
Pollution belching? Coal and oil fired plants haven't released nasty black smoke full of sulfur gases for years. Pretty much the only "bad stuff" coming out of modern petrochemical plants is CO2. Bad for the environment, yes, but I hardly think it qualifies as "pollution belching."
Do you really think people still tolerate smokestacks blasting thick, black, pungent smoke into the atmosphere? Have you ever seen a coal-fired plant?
The other major environmental impact is heat. Coal plants use river water to transfer the heat energy in their turbines. They then reject the heated water back into the river again, wreaking havoc on local ecosystems. Nuclear plants have this same problem. The only thing that sets nuclear above coal is the fact that it releases no CO2.
Having said that, I agree with you that nuclear is what we should be heading toward, at least in the interim until we figure out what the hell the real solution is.
The IT department has been forbidden to fix these things. Yes. It can easily be fixed. No. They are not allowed to.
Try thinking harder next time. Thanks.
Just for your information, the term 'regex' is a shortening of 'regular expression.' It isn't an acronym and shouldn't be written in all caps.
How can eternal life be consistent with the second law of thermodynamics? All things tend toward disorder -- to create order requires energy, and an increase in entropy which outmatches the decrease in some localized area. Hence God must have an infinite supply of energy in order to give you eternal life. Where does this energy come from?
Since when is it bold to argue from the hypothetical? People do this all the time. Nobody stated that consciousness is a form of computation. Read what the hell he said: "In this case, if one treats consciousness, conservatively, as merely a form of computation [...]"
I'd say the paragraph you quote is mostly "filler" because it presents an argument based on an unproven assumption, but that alone doesn't make it unscientific. The guy is raising an interesting idea, nothing more.
For centuries, scientists have written things like this: "If in the future we discover that X is true, then we will know that Y and Z are also true." This statement is valuable in several ways. If we find that X is true, then we immediately know Y and Z. We don't have to wait until we know X in order to work out the logic. Furthermore, if we somehow discover that Y and Z are NOT both true, then we immediately know that X cannot be true (the law of contrapositives).
So his statement is actually quite valuable. If we discover that "consciousness is infinite" (whatever that means) then we will immediately know that it must not be based on computation. If you can't see the value in that, it's only because you're stupid.
This is not science, it's a cry for attention.
You're trying to look smart. You're failing quite miserably.
Interesting idea. If the computer could simulate reality faster than reality itself unfolds, then you could use the computer to simulate itself at a faster rate than it can itself execute. And of course, this simulated super-fast computer could also simulate an even faster version of itself, etc etc. There would be no bound to how fast such a machine could compute. This is in direct violation of the results put forth in this paper.
Therefore I think we can confidently state the following:
Any computer capable of simulating a Turing-complete computational device is restricted to simulations which run slower than the machine itself can execute. You can't use a computer to simulate a faster computer. This might seem intuitively obvious, but now we have a proof of it.
Hold on right there. What have they infringed upon?
What they've done is very low and dishonest, but I highly doubt they've broken any laws or infringed on anything. I can't imagine that there is a law saying that one piece of software cannot "lie" to another -- was the kernel module Under Oath or something? (And if there was such a law, it would be a truly dangerous and stupid law.)
Because that's how C handles strings. A string is a series of non-zero bytes terminated by a zero byte.
So the short answer to your question is that the code is written in that way because it has been Ordained By God (i.e., the ISO C standards committee).
Interestingly, and had you read the article links you would have known this, Linus suggests working around this "trick" by making the license strings into Pascal-style strings where the string length is explicitly indicated by a prefix word. Doing so would cause that string to become incompatible with all other string manipulation functions so it is not something which is done lightly, or on a whim.