Someone in an earlier comment pointed out that the Barringer Crater was thought to have been made by a rock about 55 meters in diameter. I was extrapolating from that. That crater is substantially bigger than anything humans have managed including fusion bombs. But It's an arguable point, especially since I'm too lazy to do any of the math.:)
If it hit the ocean the equivalent volume of water would be displaced, and quite a bit of it would be vaporized. So I would argue that the result would be a significant tsunami (bigger than Japan? I don't know) and a change in the weather for a year or two.
If it hit the ocean anywhere near land, it would still cause significant devastation. In "Lucifer's Hammer" by Larry Niven and Jerry Pournelle, a much larger object struck the Pacific Ocean - IIRC a mile in diameter. At 30,000 MPH relative, about 8.3 miles per second, that large object went through the depth of the Pacific in something less than one second, vaporizing cubic miles of water and causing a tsunami a couple thousand feet high, striking LA and washing over the mountains into the Central Valley. This one is a tiny fraction of that one, but I suspect (without doing any math) that if it hit within a few miles of a coastline it might easily displace a volume of water equivalent to the crater it would generate on land, thereby causing a significant tsunami, and it would vaporize enough to change the weather for a year or two.
I think you are out of date. PHP has for quite a while had classes with class variables and class constants.
It also has namespaces (which AFAIK apply to classes, constants and functions but not variables). If I understand correctly, the Global context is now actually just a default namespace.
History. PHP was first developed in a world where security was not such an issue (I was using PHP 1.99s in about 1995), and was originally grown from a bunch of shell scripts. It was a simple system to solve simple problems. Present-day PHP is a vastly different language, having gone through at least two major reconstructions. But because of a desire to maintain backwards compatibility as much as possible compatible with security and other concerns, many early features have been retained, and are gradually being deprecated. The process has generally been to first provide new functionality as an option, then as the preferred approach, then standard practice, then the old feature is deprecated, and finally it is dropped from the language.
One company I am familiar with has a lot of PHP code that was originally written by a novice, running (I think) PHP 3, and used both global variables and register_globals and some other unsavory practices throughout. By the time 'real' programmers got involved there were hundreds or thousands of separate web pages that all depended on these characteristics. It's taken about three years so far for a team to gradually wean the system from these practices - there's just no budget to rewrite from scratch so it has to be done incrementally as part of the process of adding new capability and modifying existing code as needed for new business requirements. Once you have a large existing system, rebuilding from scratch is not usually a financially viable option for the average business.
IIRC, not supporting multiple inheritance was one of the primary motivations for Java. Multiple inheritance (again, IIRC) makes it impossible to avoid ambiguities that a compiler can not resolve, thus making it easy to write programs that can be very difficult to debug. I haven't looked at this stuff for 20 years, so I don't recall perzackly. Not supporting MI meant the size of the Java compiler a small fraction of the size, and much more reliable. But others here can speak to this far better than I.
Maybe you have an idea of why all the Mars rovers so far have been wheeled vehicles? I've been wondering about this for a while. Is it just timing? Are practical legged vehicles only now getting to the point of sufficient reliability?
The Economist talked about a housing bubble in 2004. They showed that, worldwide house prices were about twice what is normally justified by rentals, and predicted that if nothing else happened, it would take 14 years for rents to catch up - so don't expect your house to increase in value for that long. Of course then the money-pumpers got involved and we all know what happened next.
Some of the top paid gov employees in Massachusetts are cops - IIRC a few made more than the governor. A lot of this was overtime they picked up for sitting in a cop car with the lights on at construction zones (yes, in Massachusetts until recently ALL construction zones had to have a cop with the lights flashing, and all flaggers were cops). A year or two ago they managed to get a law passed allowing non-police to do some flagging.
Back when I travelled a lot doing sales support and also programming in the hotel rooms (sometimes all night), I got trained so that I would get on the airplane, sit down, buckle up and be asleep before we left the gate. Sometimes I woke up enough to tilt the seat back. I would wake up as we came in for a landing (each landing). I got at least 1/2 my total sleep that way, sometimes for six weeks at a time.
Near Tillamook is the Tillamook Air Museum, which is housed in a World War II blimp hangar. I wonder if the new facility is close by. The hangar might have been a useful facility but is (obviously) presently in use. Also the choice of Tillamook is interesting, with the previous construction of the blimp hangar. I wonder if the meteorological conditions in the area are good for lighter-than-air craft.
And then someone will come out with the ultimate answer to more cores: "New, Coreless Computing(TM) - no need to wonder how many cores is right for you! With our new Coreless Computing technology, you can beat all those pathetic multicore junkies!" - picture of pathetic nerd looking glumly at his now-obsolete shiny.
Of course, I have no idea what 'Coreless Computing' might be - maybe processor-per-cell memory? Neural network processors?
... Which goes right to my Brown Food theory. The BFT explains why we like brown foods - chocolate, grilled meat, tobacco (not exactly food, but it is consumed in a relevant way), all sorts of burnt stuff. All of these cause cancer, which causes us to die earlier, which makes room for the next individual. It's God's version of planned obsolescence!:D
I right-click on the login link, send the login to a new tab, login there, then reload the tab I'm on and delete the tab I logged in on. I actually have a bookmark to the login, so I can right-click on that and do the same, so I don't even lose my place on the page (except that my prefs expand more of the comments). I tried setting up the auto-login thing but it didn't seem to work any more.
Actually there is a common fallacy held by, apparently, almost everyone (including the 1% 'libertarians' of Wall Street in particular), that the 1% were the heroes of Atlas Shrugged. In both Atlas Shrugged and The Fountainhead, the heroes were the builders - the creators, who were rebelling against both the thrust toward and acceptance of mediocrity (and worse), and the powerful financial elite, who encouraged and enforced that mediocrity in order to maintain their power and money, and could/would not allow the true creative to build anything that disrupted their stable hierarchical system. The financiers were NOT the heroes, but among the chief villains. IMHO Ayn Rand would have liked Steve Jobs - not Paulson, or even Buffett.
My theory (from long ago) is as follows: "On the internet, the software is the law." IOW no matter what laws legislators may pass, those laws have no effect unless/until they are implemented in the software. What the software allows, happens.
Since then, I've become more aware of 'emergent properties' of complex adaptive systems, which are those characteristics that may arise out of the web of software and the myriad asynchronous interactions between the myriad nodes, and the influence and adaptations by humans. Unintended consequences are one such type of property. So one can also say, what the software seems to disallow, may still happen.
10 seconds with Google would have given this guy a dozen choices! hell a whole minute on the Ubuntu forums would have easily given him a dozen more, and who better than the guys that help folks with that OS?
I disagree. Google is a good place to start, but once you have a dozen choices, how do you find out the good & bad of each one, the secret tricks, and so forth? So it's good to start there but also to research other forums, and then check places like Slashdot for the latest and greatest experience. A lot of advice in old forums is out of date, often by years. Unfortunately Google is as likely to give advice from 2006 as from today. Ask Slashdot is a fertile source of good opinions by people who've 'been there, done that', and more importantly, may have done it last week, from a broader experiential spectrum that the Ubuntu forums. To me it can be like asking the guys around the lab what they think about the problem. Of course, not always...!!
Ahh, those were the days - a line to use the keypunch, then two day turnaround to find out you put a comma instead of a period. Then, find the card among 400 others, repunch the card, and wait two more days. That was how it worked at my school at crunch time. The machine had a 1 megabyte hard drive with a mean seek time of 1 second, 16K of 16-bit core, and a 1MHz clock, and a 15 minute max time before the job got dumped automatically. If you used nested macros in your assembly program it might well take 15 minutes just to assemble the program, much less actually run it!
Then I finagled access to a teletype running on a 9600 baud line to the CDC 3300, running ALGOL 68 at another university. That was much better.:)
The parable, also known as the broken window fallacy or glazier's fallacy, demonstrates how opportunity costs, as well as the law of unintended consequences, affect economic activity in ways that are "unseen" or ignored.
I think it was Niels Bohr who said "Arithmetic is an exotic form of boolean algebra, and should not be taught to children".
Teaching the old way first was counter to the whole idea, which was that it was easier, faster and more effective to teach kids to think algebraically first. Teaching arithmetic first would have been the equivalent of teaching programmers BASIC before they are allowed to learn Java, or C, or whatever.
Having said that (and reviewing the Wikipedia article), I can probably agree that the original New Math may have gone too far, too fast, and perhaps too formal (though I don't recall those being issues when I was taking it as a youngster). But I would argue that the basic idea of using an algebraic approach, simple set theory, etc. is far better than the traditional system that has been proved to be a horrific disaster for most children - as this thread discusses.
It really just started out as a 'balancing' thing (which is the essence of algebra) - putting things at different places on two sides, and figuring out what the unknown thing had to be so that balance was maintained. I don't recall any examples of the work on sets, but I think it gave me a good early understanding of sets that was beneficial ever since.
I would say the two primary criteria for 'what is news' are, "Will it affect me?" or "Is it something I can and should do something about?" Not necessarily directly - e.g. voting isn't generally a direct effect. If the story doesn't include one of these, then it's really not news, it's gossip or titillation.
Unfortunately nearly all 'news' these days is sex, car crashes or celebrity gossip - pandering to the biological drives.
On a related note, I finally understood the attraction of the gossip rags at the grocery checkout stand when I read about a study of monkeys, who had been trained to use a juice-based 'monetary system' - they could buy and sell. The researchers used the system to determine monkey preferences. They found that monkeys would pay 'money' to see pictures of the alpha members of the troop (which explains People Magazine), and pictures of naked monkey butts (which explains Penthouse and Cosmo). AFAIK they did not test pictures of monkeys being injured. That would have tested my hypothesis that the urge to see and look at car crashes is also biologically based.
Yes. Back in about 1976 Psychology Today had a pair of articles - one showed that of all professions, teachers had the highest incidence of a 'mental block' against math, and the other showed that they were successful in communicating that to their students. In Grade 3 about 50% of all students liked math. By Grade 5, only about 15% of girls and 30% of boys liked math.
In my own experience, back in the late 1950s my school was one of those working with the experimental 'New Math' from Stanford Research Institute (now SRI international) - the books were stapled together paperbacks. The New Math basically taught math from an algebraic perspective. It worked great, and it probably accelerated my own understanding. Nationwide the New Math failed, and the analysis showed that while it worked great for students the teachers just couldn't hack it. So school systems dropped it, to the lasting detriment of all students for the last four decades.
It's yet one more unfortunate result of the stultified Education establishment, along with phonics, critical thinking and other power learning tools. The system was originally developed (by Dewey's own account) not to teach but to indoctrinate good industrial workers. The entire concept of age-based class cohorts was never efficient, cost effective or productive. It is now a completely obsolete anachronism, where crowd control and logistics comprises between 75% and 85% of a given day, and actual learning the poor relation.
Slashdot Mirror
Someone in an earlier comment pointed out that the Barringer Crater was thought to have been made by a rock about 55 meters in diameter. I was extrapolating from that. That crater is substantially bigger than anything humans have managed including fusion bombs. But It's an arguable point, especially since I'm too lazy to do any of the math. :)
If it hit the ocean the equivalent volume of water would be displaced, and quite a bit of it would be vaporized. So I would argue that the result would be a significant tsunami (bigger than Japan? I don't know) and a change in the weather for a year or two.
If it hit the ocean anywhere near land, it would still cause significant devastation. In "Lucifer's Hammer" by Larry Niven and Jerry Pournelle, a much larger object struck the Pacific Ocean - IIRC a mile in diameter. At 30,000 MPH relative, about 8.3 miles per second, that large object went through the depth of the Pacific in something less than one second, vaporizing cubic miles of water and causing a tsunami a couple thousand feet high, striking LA and washing over the mountains into the Central Valley. This one is a tiny fraction of that one, but I suspect (without doing any math) that if it hit within a few miles of a coastline it might easily displace a volume of water equivalent to the crater it would generate on land, thereby causing a significant tsunami, and it would vaporize enough to change the weather for a year or two.
I think you are out of date. PHP has for quite a while had classes with class variables and class constants.
It also has namespaces (which AFAIK apply to classes, constants and functions but not variables). If I understand correctly, the Global context is now actually just a default namespace.
History. PHP was first developed in a world where security was not such an issue (I was using PHP 1.99s in about 1995), and was originally grown from a bunch of shell scripts. It was a simple system to solve simple problems. Present-day PHP is a vastly different language, having gone through at least two major reconstructions. But because of a desire to maintain backwards compatibility as much as possible compatible with security and other concerns, many early features have been retained, and are gradually being deprecated. The process has generally been to first provide new functionality as an option, then as the preferred approach, then standard practice, then the old feature is deprecated, and finally it is dropped from the language.
One company I am familiar with has a lot of PHP code that was originally written by a novice, running (I think) PHP 3, and used both global variables and register_globals and some other unsavory practices throughout. By the time 'real' programmers got involved there were hundreds or thousands of separate web pages that all depended on these characteristics. It's taken about three years so far for a team to gradually wean the system from these practices - there's just no budget to rewrite from scratch so it has to be done incrementally as part of the process of adding new capability and modifying existing code as needed for new business requirements. Once you have a large existing system, rebuilding from scratch is not usually a financially viable option for the average business.
IIRC, not supporting multiple inheritance was one of the primary motivations for Java. Multiple inheritance (again, IIRC) makes it impossible to avoid ambiguities that a compiler can not resolve, thus making it easy to write programs that can be very difficult to debug. I haven't looked at this stuff for 20 years, so I don't recall perzackly. Not supporting MI meant the size of the Java compiler a small fraction of the size, and much more reliable. But others here can speak to this far better than I.
Maybe you have an idea of why all the Mars rovers so far have been wheeled vehicles? I've been wondering about this for a while. Is it just timing? Are practical legged vehicles only now getting to the point of sufficient reliability?
The Economist talked about a housing bubble in 2004. They showed that, worldwide house prices were about twice what is normally justified by rentals, and predicted that if nothing else happened, it would take 14 years for rents to catch up - so don't expect your house to increase in value for that long. Of course then the money-pumpers got involved and we all know what happened next.
Some of the top paid gov employees in Massachusetts are cops - IIRC a few made more than the governor. A lot of this was overtime they picked up for sitting in a cop car with the lights on at construction zones (yes, in Massachusetts until recently ALL construction zones had to have a cop with the lights flashing, and all flaggers were cops). A year or two ago they managed to get a law passed allowing non-police to do some flagging.
Back when I travelled a lot doing sales support and also programming in the hotel rooms (sometimes all night), I got trained so that I would get on the airplane, sit down, buckle up and be asleep before we left the gate. Sometimes I woke up enough to tilt the seat back. I would wake up as we came in for a landing (each landing). I got at least 1/2 my total sleep that way, sometimes for six weeks at a time.
Near Tillamook is the Tillamook Air Museum, which is housed in a World War II blimp hangar. I wonder if the new facility is close by. The hangar might have been a useful facility but is (obviously) presently in use. Also the choice of Tillamook is interesting, with the previous construction of the blimp hangar. I wonder if the meteorological conditions in the area are good for lighter-than-air craft.
And then someone will come out with the ultimate answer to more cores: "New, Coreless Computing(TM) - no need to wonder how many cores is right for you! With our new Coreless Computing technology, you can beat all those pathetic multicore junkies!" - picture of pathetic nerd looking glumly at his now-obsolete shiny.
Of course, I have no idea what 'Coreless Computing' might be - maybe processor-per-cell memory? Neural network processors?
... Which goes right to my Brown Food theory. The BFT explains why we like brown foods - chocolate, grilled meat, tobacco (not exactly food, but it is consumed in a relevant way), all sorts of burnt stuff. All of these cause cancer, which causes us to die earlier, which makes room for the next individual. It's God's version of planned obsolescence! :D
I right-click on the login link, send the login to a new tab, login there, then reload the tab I'm on and delete the tab I logged in on. I actually have a bookmark to the login, so I can right-click on that and do the same, so I don't even lose my place on the page (except that my prefs expand more of the comments). I tried setting up the auto-login thing but it didn't seem to work any more.
Actually there is a common fallacy held by, apparently, almost everyone (including the 1% 'libertarians' of Wall Street in particular), that the 1% were the heroes of Atlas Shrugged. In both Atlas Shrugged and The Fountainhead, the heroes were the builders - the creators, who were rebelling against both the thrust toward and acceptance of mediocrity (and worse), and the powerful financial elite, who encouraged and enforced that mediocrity in order to maintain their power and money, and could/would not allow the true creative to build anything that disrupted their stable hierarchical system. The financiers were NOT the heroes, but among the chief villains. IMHO Ayn Rand would have liked Steve Jobs - not Paulson, or even Buffett.
My theory (from long ago) is as follows: "On the internet, the software is the law." IOW no matter what laws legislators may pass, those laws have no effect unless/until they are implemented in the software. What the software allows, happens.
Since then, I've become more aware of 'emergent properties' of complex adaptive systems, which are those characteristics that may arise out of the web of software and the myriad asynchronous interactions between the myriad nodes, and the influence and adaptations by humans. Unintended consequences are one such type of property. So one can also say, what the software seems to disallow, may still happen.
10 seconds with Google would have given this guy a dozen choices! hell a whole minute on the Ubuntu forums would have easily given him a dozen more, and who better than the guys that help folks with that OS?
I disagree. Google is a good place to start, but once you have a dozen choices, how do you find out the good & bad of each one, the secret tricks, and so forth? So it's good to start there but also to research other forums, and then check places like Slashdot for the latest and greatest experience. A lot of advice in old forums is out of date, often by years. Unfortunately Google is as likely to give advice from 2006 as from today. Ask Slashdot is a fertile source of good opinions by people who've 'been there, done that', and more importantly, may have done it last week, from a broader experiential spectrum that the Ubuntu forums. To me it can be like asking the guys around the lab what they think about the problem. Of course, not always...!!
Ahh, those were the days - a line to use the keypunch, then two day turnaround to find out you put a comma instead of a period. Then, find the card among 400 others, repunch the card, and wait two more days. That was how it worked at my school at crunch time. The machine had a 1 megabyte hard drive with a mean seek time of 1 second, 16K of 16-bit core, and a 1MHz clock, and a 15 minute max time before the job got dumped automatically. If you used nested macros in your assembly program it might well take 15 minutes just to assemble the program, much less actually run it!
Then I finagled access to a teletype running on a 9600 baud line to the CDC 3300, running ALGOL 68 at another university. That was much better. :)
The average slashdotter probably pays more for phone+internet+pizza than the median world per capita income (about $1000/yr)
The excuse that they create jobs, in cleaning them up, is not a strong one, since by that same logic you could also make work by smashing them.
Yes, this is the Broken Window Fallacy.
To quote:
The parable, also known as the broken window fallacy or glazier's fallacy, demonstrates how opportunity costs, as well as the law of unintended consequences, affect economic activity in ways that are "unseen" or ignored.
Sorry, it was a while back and I don't recall the particulars. But it appears that you're on the right track.
I think it was Niels Bohr who said "Arithmetic is an exotic form of boolean algebra, and should not be taught to children".
Teaching the old way first was counter to the whole idea, which was that it was easier, faster and more effective to teach kids to think algebraically first. Teaching arithmetic first would have been the equivalent of teaching programmers BASIC before they are allowed to learn Java, or C, or whatever.
Having said that (and reviewing the Wikipedia article), I can probably agree that the original New Math may have gone too far, too fast, and perhaps too formal (though I don't recall those being issues when I was taking it as a youngster). But I would argue that the basic idea of using an algebraic approach, simple set theory, etc. is far better than the traditional system that has been proved to be a horrific disaster for most children - as this thread discusses.
It really just started out as a 'balancing' thing (which is the essence of algebra) - putting things at different places on two sides, and figuring out what the unknown thing had to be so that balance was maintained. I don't recall any examples of the work on sets, but I think it gave me a good early understanding of sets that was beneficial ever since.
IMHO it is. If I take a used carburetor out of a wrecked car, and put it on my that needs a replacement, isn't that recycling?
I would say the two primary criteria for 'what is news' are, "Will it affect me?" or "Is it something I can and should do something about?" Not necessarily directly - e.g. voting isn't generally a direct effect. If the story doesn't include one of these, then it's really not news, it's gossip or titillation.
Unfortunately nearly all 'news' these days is sex, car crashes or celebrity gossip - pandering to the biological drives.
On a related note, I finally understood the attraction of the gossip rags at the grocery checkout stand when I read about a study of monkeys, who had been trained to use a juice-based 'monetary system' - they could buy and sell. The researchers used the system to determine monkey preferences. They found that monkeys would pay 'money' to see pictures of the alpha members of the troop (which explains People Magazine), and pictures of naked monkey butts (which explains Penthouse and Cosmo). AFAIK they did not test pictures of monkeys being injured. That would have tested my hypothesis that the urge to see and look at car crashes is also biologically based.
Yes. Back in about 1976 Psychology Today had a pair of articles - one showed that of all professions, teachers had the highest incidence of a 'mental block' against math, and the other showed that they were successful in communicating that to their students. In Grade 3 about 50% of all students liked math. By Grade 5, only about 15% of girls and 30% of boys liked math.
In my own experience, back in the late 1950s my school was one of those working with the experimental 'New Math' from Stanford Research Institute (now SRI international) - the books were stapled together paperbacks. The New Math basically taught math from an algebraic perspective. It worked great, and it probably accelerated my own understanding. Nationwide the New Math failed, and the analysis showed that while it worked great for students the teachers just couldn't hack it. So school systems dropped it, to the lasting detriment of all students for the last four decades.
It's yet one more unfortunate result of the stultified Education establishment, along with phonics, critical thinking and other power learning tools. The system was originally developed (by Dewey's own account) not to teach but to indoctrinate good industrial workers. The entire concept of age-based class cohorts was never efficient, cost effective or productive. It is now a completely obsolete anachronism, where crowd control and logistics comprises between 75% and 85% of a given day, and actual learning the poor relation.