goto is OK because it can do something in any language that offers it, that no other construct in that language allows.
You can jump from inside the middle of one nested set of loops and/or tests directly into the middle of another set.
(USE WITH CARE!)
Without goto, you have to set a flag and then test that flag multiple times to do the equivalent. What a waste of time!
Quite a few years ago, there was a brief popularity of something called VRAM (video ram) that had memory cells specifically designed with one input line and TWO output lines. The idea was that the part of the hardware needing to construct an image for the screen ONLY needed to read memory, while the system responsible for creating the image needed both read and write access. Ever since then, I've wondered why they don't use this kind of memory in multi-processor systems, for communication between processors, such that Processor A has read/write access to a block of VRAM, to give info to Processor B (it has read-access only), while Processor B has read/write access to a different block of VRAM, to give info to Processor A (it has read-access only).
OK, I grant that one needs to have a certain amount of interest in learning.
Can we assume that the ones who aren't interested are also not too likely to try to obtain hardware and software, even if free?
I am shocked that nobody in the messages leading to this one mentioned the simple fact that once you HAVE software and hardware, you can learn to use it. Free just makes it easier for more people to learn, than costly.
Why do you need to use a Web site, anyway? Why not carry your files around in a Flash device, and upload directly to the client?
The Square Grid
on
Ask Sid Meier
·
· Score: 5, Interesting
Why do you keep using a square grid (however distorted by perspective) when a hexagon grid is known to be more accurate for movement across a landscape? I do understand that this would influence a number of other things, such as the Local City Area would be 18 surrounding hexagons instead of 20 nearby squares, and that when surrounding an enemy you only have 6 ways to attack instead of 8, but those are not insurmountable issues. For example, if the SCALE of the grid compared to the map was shrunk a bit, you could "enlarge" the Local City Area by another ring of hexagons, for 36 total surrounding cells. Productivity in every cell is merely set a little lower than before. In combat distance weapons having a range of 2 cells could allow an enemy to be surrounded by up to 18 of your units (probably only after Cannons are invented). Alternately, simple construction of roads and railroads already allow distant units to engage an enemy; why can't building roads and railroads near a city extend the Local Area of that city? And other ways of accommodating a hexagon grid are possible, I'm sure. So, why not?
Even without trolling NASA, there might be reason to do what the original poster suggested.
Rember Global Warming? If the oceans rise 40 feet, where will Cape Canaveral be?
There was an article several years ago in the science-fiction/science-fact magazine ANALOG titled, "Defeating the Son of Andrew". It suggested building a huge tall tower designed to transport warm moist air near ground level (of ocean) upward, where condensation and wind-generation would happen inside the tower (source of fresh water and energy!), and because it is supposed to draw warm moist air from miles around, any approaching hurricane will be out of luck -- the energy that would have helped feed the hurricane has already been extracted.
You may be aware that out there in the PC world you can buy special keyboards of all sorts. There is a type that uses "chording", so that you have to press two or three keys at the same time to generate a character. It is my understanding that after you get used to it, chording is a reasonably efficient input method (but have no personal experience to back up the claim). The main advantage, though, is that the keyboard is quite small (has many fewer keys than a standard keyboard). It seems to me that with the limited space available on a phone, implementing chording would be a natural. So, if any manufacturer out there has done it, then for you to find it and get it would be a possible recommendation.
That's BAD! Total energy efficiency, if internal combustion is used, is horrible:
The figures I have to work with are:
50% conversion efficiency of fuel energy to electricity in large power plant.
66% conversion efficiency of electrolysis to make hydrogen.
66% conversion efficiency of making electricity in fuel cell.
95% conversion efficiency of electricity to motive power.
35% conversion efficiency of internal combustion to motive power.
SO: Total efficiency of a direct-burning fossil-fuel car is 35%
Total efficiency of fuel cell car is computed as 50% x 66% x 66% x 95%, or about 21%
Total efficiency of a hydrogen internal combustion car is 50% x 66% x 35% or about 12%.
A dictation recorder, for example. Sure, tapes are a drag to listen all the way through, to make sure you get reminded of everything on it.
So...I bet as soon as someone rigs up one with a hard disk drive and a voice-controlled filing system, saving AND quickly finding recorded memos will attract a lot of buyers.
Thanks for the comments, folks!
Yes, I am aware of the problem posed by sudden entry from vacuum to atmosphere, even if the place where that happens is, say, the 20,000 feet of Mt. McKinley.
So, I have concocted a mad space-mountain idea, for your entertainment, and to deal with that objection.:)
Electromagnetic launchers are practical NOW. "Just accelerate the space cargo in a vacuum tube until escape velocity is achieved, while climbing a high mountain." Only one key technology has been needed, and it got invented just a couple years ago. At the END of that vacuum tube, a means is needed to keep the atmosphere from rushing in while still letting the cargo exit. The plasma valve is the answer to that problem.
You are overlooking the "overall efficiency" factor. Inside a fluorescent light some energy is wasted. Some goes to make the mercury emit UV. Some, not all, of the UV is absorbed by the flurescent phosphors (some is absorbed by the glass of the bulb). Some of the ordinary light fluoresced is radiated through the glass; some is absorbed by the glass -- and some is radiated inside the tube, toward the (opaque!) fluorescent coating on the other side of the tube. There is PLENTY of opportunity here for phosphorescent materials to collect energy to re-emit when the power is off!
Next, it might be noted that ordinary AC already fluctuates between max power and zero power; ordinary fluorescent bulbs are already turning on and off rapidly. The parent posting is simply suggesting that with phosphorescent bulbs, a lesser rate can still work (say 30Hz instead of 60hz, and of course a square wave and not a sine wave is specified.
"...make it illegal to produce 'circumvention devices' for protected works."
If I buy an good-quality book, the data is "protected" reasonably well for several hundred years, provided I don't seriously abuse it like throwing into a fireplace. But if I buy a good-quality CD or DVD, somehow it always picks up scratches that eventually makes the data lost. Where is the "protection" of the data???
Dare we say that the companies making those discs have deliberately CIRCUMVENTED the ability of the discs to protect data for centuries? Dare we therefore throw all their CEOs in jail for illegal activities?
That is, do you you also want basic connectivity and setup info? (Installing LAN cards, or getting motherboards with builtin LAN, is like Step Zero.)
Anyway, remember the Internet as a source of data. Sometimes this is better than books, and sometimes not, due to how data-condensing (less pages to look through). For a Windows setup, here is a tutorial. For a Linux setup, other places certainly exist. Choosing the network environment is probably Step One....
Per the first question in this thread, NO, this suit is like complaining about a "for sale" sign in a store window being photographed, saved for years, and later viewed. After all, almost everything (there have been a few mistakes) posted on the Web that is publicly accessible was put there to be seen!
Re:I agree. The very idea of such a penalty is evi
on
Death Penalty For Hackers?
·
· Score: 5, Insightful
If we punish with the death penalty those whose actions upset the lives of many many other people, and also cost lots and lots, then there is a long list of people who qualify. CEOs who rob pension funds, for example. Various politicians....
Let's see, aren't quantum computers supposed to operate at millions or billions or even trillions of operations per second? I'd say just make sure every single qbit gets USED within a second, and then store the next uncertain piece of data in it, for the next part of the overall calculation. That is, the solution to this problem is not to be found in hardware (besides MASSIVE parallelism to fill lots of qbits in minimum time), but in appropriate programming.
You didn't indicate any question about what archival-quality digital storage medium might be best. Remember CD rot? Magnetic tape/floppy wear & tear? Hard drive crashes? That's why my personal choice is magneto-optical. Available in 5.25" and 3.5" sizes, the disks are removable like floppies and have protective shells. The disk itself is mostly polycarbonate ("Lexan") and the data layer can only be altered if the temperature rises near the Curie Point for the media (protect from fire, obviously!). They use a laser to get the heat to let data be written, inside a changing magnetic field (and a lower-power laser setting to read the data). Geologists studying the history of the Earth's magnetic field can find useful data saved/fixed in lava flows from millions of years ago. Data retention doesn't get much better than that (currently actually guaranteed for 40 or 50 years, but every few years when I check, the number goes up). So far each new higher-capacity generation of magneto-optical drive is backward compatible with all previous generations of disks, so if your drive dies, you can replace it and still access your data. Also, most disks are not WORM types (write once read many); they can be cleanly rewritten any number of times, as needed. [Ummm...a final note, the 3.5" drives only write on one side of a disk, max current capacity about 2.3Gb, while the 5.25" drives are 4 or 5 times as expensive, but can write on either side of a disk (which must be manually flipped) and max capacity is over 9Gb.]
Re:These guys must not be real nerds
on
Leap Second This Year
·
· Score: 4, Interesting
The thing that bothers me is, when that big quake in Indonesia went off last year and caused that big tsunami, they talked about how the Earth's rotation SPEEDED UP. If it has already slowed down again in only one year, such that a leap second is needed, then that implies some other place has been bulging and may be about to give way. So, any Slashdotters who can pass this inference on to the geology folks, please do so pronto! Thanks!
You CAN'T control what people think. You CAN'T control the urge to know. You CAN'T make people believe something is bad just because you say it is bad. You have to provide convincing evidence.
For example, over in Denmark in the 1970s they dropped most restrictions regarding pornography. After 30 years, the nation did NOT turn into a gang of rapists. They probably mentally filter out billboards featuring naked people just like they filter out any other uninteresting advertising. So, where is the evidence to support Chinese government (or any other government) claims of bad things associated with pornography? It's in the unnecessary restrictions! Forcing it underground just makes it more interesting ("I want to see what they don't want me to see, to find out why they don't want me to see it!"). Exposing it takes away that incentive, and people tend to ignore what not's immediately relevant. A curb of freedom is ALWAYS immediately relevant!
Now, you CAN influence what people do with what they know. Does the Chinese Constitution have any mechanism whereby it might be Amended, like the U.S. (and other) Constitutions? If not, then whatever curbs of freedom built into the Chinese Constitution will eventually and inevitably boil over into an ugly revolution. The leadership over there is going to find out, one way or another, just what The People can do. So, they can either plan on an England-like open system (which started with the Magna Charta), or they can keep a France-like repressive system (which ended with beheadings).
Slashdot Mirror
goto is OK because it can do something in any language that offers it, that no other construct in that language allows.
You can jump from inside the middle of one nested set of loops and/or tests directly into the middle of another set.
(USE WITH CARE!)
Without goto, you have to set a flag and then test that flag multiple times to do the equivalent. What a waste of time!
Quite a few years ago, there was a brief popularity of something called VRAM (video ram) that had memory cells specifically designed with one input line and TWO output lines. The idea was that the part of the hardware needing to construct an image for the screen ONLY needed to read memory, while the system responsible for creating the image needed both read and write access. Ever since then, I've wondered why they don't use this kind of memory in multi-processor systems, for communication between processors, such that Processor A has read/write access to a block of VRAM, to give info to Processor B (it has read-access only), while Processor B has read/write access to a different block of VRAM, to give info to Processor A (it has read-access only).
OK, I grant that one needs to have a certain amount of interest in learning. Can we assume that the ones who aren't interested are also not too likely to try to obtain hardware and software, even if free?
I am shocked that nobody in the messages leading to this one mentioned the simple fact that once you HAVE software and hardware, you can learn to use it. Free just makes it easier for more people to learn, than costly.
Why do you need to use a Web site, anyway? Why not carry your files around in a Flash device, and upload directly to the client?
Why do you keep using a square grid (however distorted by perspective) when a hexagon grid is known to be more accurate for movement across a landscape? I do understand that this would influence a number of other things, such as the Local City Area would be 18 surrounding hexagons instead of 20 nearby squares, and that when surrounding an enemy you only have 6 ways to attack instead of 8, but those are not insurmountable issues. For example, if the SCALE of the grid compared to the map was shrunk a bit, you could "enlarge" the Local City Area by another ring of hexagons, for 36 total surrounding cells. Productivity in every cell is merely set a little lower than before. In combat distance weapons having a range of 2 cells could allow an enemy to be surrounded by up to 18 of your units (probably only after Cannons are invented). Alternately, simple construction of roads and railroads already allow distant units to engage an enemy; why can't building roads and railroads near a city extend the Local Area of that city? And other ways of accommodating a hexagon grid are possible, I'm sure. So, why not?
Even without trolling NASA, there might be reason to do what the original poster suggested. Rember Global Warming? If the oceans rise 40 feet, where will Cape Canaveral be?
There was an article several years ago in the science-fiction/science-fact magazine ANALOG titled, "Defeating the Son of Andrew". It suggested building a huge tall tower designed to transport warm moist air near ground level (of ocean) upward, where condensation and wind-generation would happen inside the tower (source of fresh water and energy!), and because it is supposed to draw warm moist air from miles around, any approaching hurricane will be out of luck -- the energy that would have helped feed the hurricane has already been extracted.
You may be aware that out there in the PC world you can buy special keyboards of all sorts. There is a type that uses "chording", so that you have to press two or three keys at the same time to generate a character. It is my understanding that after you get used to it, chording is a reasonably efficient input method (but have no personal experience to back up the claim). The main advantage, though, is that the keyboard is quite small (has many fewer keys than a standard keyboard). It seems to me that with the limited space available on a phone, implementing chording would be a natural. So, if any manufacturer out there has done it, then for you to find it and get it would be a possible recommendation.
That's BAD! Total energy efficiency, if internal combustion is used, is horrible:
The figures I have to work with are:
50% conversion efficiency of fuel energy to electricity in large power plant.
66% conversion efficiency of electrolysis to make hydrogen.
66% conversion efficiency of making electricity in fuel cell.
95% conversion efficiency of electricity to motive power.
35% conversion efficiency of internal combustion to motive power.
SO: Total efficiency of a direct-burning fossil-fuel car is 35%
Total efficiency of fuel cell car is computed as 50% x 66% x 66% x 95%, or about 21%
Total efficiency of a hydrogen internal combustion car is 50% x 66% x 35% or about 12%.
A dictation recorder, for example. Sure, tapes are a drag to listen all the way through, to make sure you get reminded of everything on it.
So...I bet as soon as someone rigs up one with a hard disk drive and a voice-controlled filing system, saving AND quickly finding recorded memos will attract a lot of buyers.
It reminds me of an old arcade game called "Night Driver"
Thanks for the comments, folks!
:)
Yes, I am aware of the problem posed by sudden entry from vacuum to atmosphere, even if the place where that happens is, say, the 20,000 feet of Mt. McKinley.
So, I have concocted a mad space-mountain idea, for your entertainment, and to deal with that objection.
I bet it might make a REALLY good encryption trick, too!
Electromagnetic launchers are practical NOW. "Just accelerate the space cargo in a vacuum tube until escape velocity is achieved, while climbing a high mountain." Only one key technology has been needed, and it got invented just a couple years ago. At the END of that vacuum tube, a means is needed to keep the atmosphere from rushing in while still letting the cargo exit. The plasma valve is the answer to that problem.
You are overlooking the "overall efficiency" factor. Inside a fluorescent light some energy is wasted. Some goes to make the mercury emit UV. Some, not all, of the UV is absorbed by the flurescent phosphors (some is absorbed by the glass of the bulb). Some of the ordinary light fluoresced is radiated through the glass; some is absorbed by the glass -- and some is radiated inside the tube, toward the (opaque!) fluorescent coating on the other side of the tube. There is PLENTY of opportunity here for phosphorescent materials to collect energy to re-emit when the power is off!
Next, it might be noted that ordinary AC already fluctuates between max power and zero power; ordinary fluorescent bulbs are already turning on and off rapidly. The parent posting is simply suggesting that with phosphorescent bulbs, a lesser rate can still work (say 30Hz instead of 60hz, and of course a square wave and not a sine wave is specified.
"...make it illegal to produce 'circumvention devices' for protected works."
If I buy an good-quality book, the data is "protected" reasonably well for several hundred years, provided I don't seriously abuse it like throwing into a fireplace. But if I buy a good-quality CD or DVD, somehow it always picks up scratches that eventually makes the data lost. Where is the "protection" of the data???
Dare we say that the companies making those discs have deliberately CIRCUMVENTED the ability of the discs to protect data for centuries? Dare we therefore throw all their CEOs in jail for illegal activities?
That is, do you you also want basic connectivity and setup info? (Installing LAN cards, or getting motherboards with builtin LAN, is like Step Zero.) Anyway, remember the Internet as a source of data. Sometimes this is better than books, and sometimes not, due to how data-condensing (less pages to look through). For a Windows setup, here is a tutorial. For a Linux setup, other places certainly exist. Choosing the network environment is probably Step One....
Per the first question in this thread, NO, this suit is like complaining about a "for sale" sign in a store window being photographed, saved for years, and later viewed. After all, almost everything (there have been a few mistakes) posted on the Web that is publicly accessible was put there to be seen!
If we punish with the death penalty those whose actions upset the lives of many many other people, and also cost lots and lots, then there is a long list of people who qualify. CEOs who rob pension funds, for example. Various politicians....
Let's see, aren't quantum computers supposed to operate at millions or billions or even trillions of operations per second? I'd say just make sure every single qbit gets USED within a second, and then store the next uncertain piece of data in it, for the next part of the overall calculation. That is, the solution to this problem is not to be found in hardware (besides MASSIVE parallelism to fill lots of qbits in minimum time), but in appropriate programming.
You didn't indicate any question about what archival-quality digital storage medium might be best. Remember CD rot? Magnetic tape/floppy wear & tear? Hard drive crashes? That's why my personal choice is magneto-optical. Available in 5.25" and 3.5" sizes, the disks are removable like floppies and have protective shells. The disk itself is mostly polycarbonate ("Lexan") and the data layer can only be altered if the temperature rises near the Curie Point for the media (protect from fire, obviously!). They use a laser to get the heat to let data be written, inside a changing magnetic field (and a lower-power laser setting to read the data). Geologists studying the history of the Earth's magnetic field can find useful data saved/fixed in lava flows from millions of years ago. Data retention doesn't get much better than that (currently actually guaranteed for 40 or 50 years, but every few years when I check, the number goes up). So far each new higher-capacity generation of magneto-optical drive is backward compatible with all previous generations of disks, so if your drive dies, you can replace it and still access your data. Also, most disks are not WORM types (write once read many); they can be cleanly rewritten any number of times, as needed. [Ummm...a final note, the 3.5" drives only write on one side of a disk, max current capacity about 2.3Gb, while the 5.25" drives are 4 or 5 times as expensive, but can write on either side of a disk (which must be manually flipped) and max capacity is over 9Gb.]
The thing that bothers me is, when that big quake in Indonesia went off last year and caused that big tsunami, they talked about how the Earth's rotation SPEEDED UP. If it has already slowed down again in only one year, such that a leap second is needed, then that implies some other place has been bulging and may be about to give way. So, any Slashdotters who can pass this inference on to the geology folks, please do so pronto! Thanks!
You CAN'T control what people think. You CAN'T control the urge to know. You CAN'T make people believe something is bad just because you say it is bad. You have to provide convincing evidence.
For example, over in Denmark in the 1970s they dropped most restrictions regarding pornography. After 30 years, the nation did NOT turn into a gang of rapists. They probably mentally filter out billboards featuring naked people just like they filter out any other uninteresting advertising. So, where is the evidence to support Chinese government (or any other government) claims of bad things associated with pornography? It's in the unnecessary restrictions! Forcing it underground just makes it more interesting ("I want to see what they don't want me to see, to find out why they don't want me to see it!"). Exposing it takes away that incentive, and people tend to ignore what not's immediately relevant. A curb of freedom is ALWAYS immediately relevant!
Now, you CAN influence what people do with what they know. Does the Chinese Constitution have any mechanism whereby it might be Amended, like the U.S. (and other) Constitutions? If not, then whatever curbs of freedom built into the Chinese Constitution will eventually and inevitably boil over into an ugly revolution. The leadership over there is going to find out, one way or another, just what The People can do. So, they can either plan on an England-like open system (which started with the Magna Charta), or they can keep a France-like repressive system (which ended with beheadings).
Because it offers something that can be misused, of course, like P2P software.