Check out the writings of Dr William Kahan. One of the men behind the IEEE floating-point standard. Read "How JAVA's Floating-Point Hurts Everyone Everywhere".
http://www.cs.berkeley.edu/~wkahan/
This paper was written on July 30, 1998, and a lot has changed in Java since. Perhaps it is time to reevaluate what you know, just like Dr Kahan thinks everybody should do with regards to what they learned from textbooks about floating point maths?
For speed, Fortran is still best. Most enginering codes are in Fortran.
Although not related to speed, I find it interesting how Dr Kahan all the way through his paper picks faults with the way that Fortran does things, and saying that Java shouldn't have adopted the same way of doing it.
Here is what Dr Kahan writes in the paper on what should be done to fix Java floating point problems:
"The first step with the least cost and biggest payoff is to abandon Fortran-like bottom-up floating-point semantics, and adopt Kernighan-Ritchie C floating-point semantics."
So first you say to go have a look at what is wrong with Java, and then you say that the best language to use the one that your own reference says is broken. Way to go!
a trade off for having somewhere to put their next 1.6 billion people. The moon may very well be a possibility.
No it isn't. Space travel will never ever be a solution to population growth. There will never ever be enough energy or orbiters for that matter to move a significant number of people off-planet. Everybody keeps saying this but it just isn't true.
For instance, say you built a space plane carrying 400 people at a time, equivalent to our current 747 Jumbos. If you want to move 1 million people that way you have to make 2500 flights, if you want to move 10 million then 25,000 flights, 100 million (hey, something that might actually be noticed!) 250,000 flights! And remember, these aren't your short hops to visit grandma, these are flights that eventually will have to give a person + gear escape velocity.
If you want to move 100 million people that way in a year you have to make around 685 flights a day. That is a lot of flights going into space. And in the meantime everybody else just keeps on reproducing...
Just face it, space is not and will never be (at least in our lifetime and the lifetimes of the next 10 generations or so) a solution to over population down here.
You don't have to worry about squeezing four lanes of traffic down to one lane to go over a 45 mph bridge.
Well, you do actually. Because of the safety margins involved there are 'lanes' in the sky as well, which is why there are lots of air traffic controllers at airports getting ulcers. Unless the current air traffic control model changes radically you are not going to have any flying cars at all, since it would require far too many air traffic controllers, and the complexity of handling 1 million flying cars at rush hour over large cities is going to be pretty bad.
Also, ever get delayed on landing or takeoff because your flight can't get a slot? Same thing will happen when everybody have flying cars since you wont be allowed to just land it anywhere.
And finally, if things get too congested at 100 feet, rise to 150 feet and go over it.
Um, maybe you should add a 0 or two to those numbers, I certainly wouldn't feel very safe travelling at over 250mph at 100 feet, or having things zipping by my office window at at those speeds.
Most likely you wont be allowed to fly your car yourself, it will all be flown by computers, and computers will do all the air traffic control. To develop and deploy such a complex system will take several decades IMHO. You probably have more of a chance of getting to the moon first, since that is just extrapolation of current working technology.
CowboyNeal, please, why did you have involve the X-Prize in the post? The launch in November is not to try and win the X-Prize, and as far as I know they are not participating in the Ansari X-Prize at all. It's just another company getting in on putting payloads in space, and not even human payloads.
Thats probable what most of the crowd here would use.
Is it? Why would anybody use JDS when you have Debian (disclaimer: other dists are available)?
SunRay (at least the no-monitor version) is a super sweet piece of kit, it was my work desktop for a year and I loved it. Up until now it has just been a shame that you have to have Solaris installed to run it.
There is also a growing body of evidence that pollution is bad (prior to recently, it was purely conjecture).
An there I was going around believing that pollution was bad!
pollution
n 1: undesirable state of the natural environment being
contaminated with harmful substances as a consequence of
human activities
Hey ho, I guess we can all breathe easy now that we know that the next oil tanker going to the bottom or releasing CFC's into the atmosphere wont be a problem, because pollution has never been proven to be bad!
Re:We don't use oil for Electricity
on
Out of Gas
·
· Score: 1
Are you kidding? Was this supposed to have been moderated Funny and not Insightful perhaps?
100 years is nothing! We have been using oil for about as long running our combustion engines, and we are running out, do you want the same thing to happen again to your grandchildrens children?
And burning coal is one of the worst pollutants there is, leading to acid rain, increased greenhouse effect, smog, etc. Or maybe you would like your kids to have to constantly puff on their asthma inhaler while hauling their decomposing personal belongings away from a flooded house in acid rain? Yeah, that sounds really good, especially since they managed to have enough food that long after all the billions others died from starvation when the crops failed.
I for one certainly look forward to living out my life in a dark acid wasteland.
Slashdot Mirror
But maybe one application would be creating insanely large solar sails that fold up extremely small.
;)
Aha, but could you fold it in half more than 7 times?
Check out the writings of Dr William Kahan. One of the men behind the IEEE floating-point standard.
Read "How JAVA's Floating-Point Hurts Everyone Everywhere".
http://www.cs.berkeley.edu/~wkahan/
This paper was written on July 30, 1998, and a lot has changed in Java since. Perhaps it is time to reevaluate what you know, just like Dr Kahan thinks everybody should do with regards to what they learned from textbooks about floating point maths?
For speed, Fortran is still best. Most enginering codes are in Fortran.
Although not related to speed, I find it interesting how Dr Kahan all the way through his paper picks faults with the way that Fortran does things, and saying that Java shouldn't have adopted the same way of doing it.
Here is what Dr Kahan writes in the paper on what should be done to fix Java floating point problems:
"The first step with the least cost and biggest payoff is to abandon Fortran-like bottom-up floating-point semantics, and adopt Kernighan-Ritchie C floating-point semantics."
So first you say to go have a look at what is wrong with Java, and then you say that the best language to use the one that your own reference says is broken. Way to go!
Which line 3 ends up being:
CrazyObjectNumber c = ((a = a.multiply(b)).add(53)).clone();
Um, only if you don't know what you are doing.
If you do know what you are doing and have a sensibly developed library that is using immutable objects it ends up being:
CrazyObjectNumber c = a.multiply(b).add(53);
Looks pretty clear to me.
a trade off for having somewhere to put their next 1.6 billion people. The moon may very well be a possibility.
No it isn't. Space travel will never ever be a solution to population growth. There will never ever be enough energy or orbiters for that matter to move a significant number of people off-planet. Everybody keeps saying this but it just isn't true.
For instance, say you built a space plane carrying 400 people at a time, equivalent to our current 747 Jumbos. If you want to move 1 million people that way you have to make 2500 flights, if you want to move 10 million then 25,000 flights, 100 million (hey, something that might actually be noticed!) 250,000 flights! And remember, these aren't your short hops to visit grandma, these are flights that eventually will have to give a person + gear escape velocity.
If you want to move 100 million people that way in a year you have to make around 685 flights a day. That is a lot of flights going into space. And in the meantime everybody else just keeps on reproducing...
Just face it, space is not and will never be (at least in our lifetime and the lifetimes of the next 10 generations or so) a solution to over population down here.
You don't have to worry about squeezing four lanes of traffic down to one lane to go over a 45 mph bridge.
Well, you do actually. Because of the safety margins involved there are 'lanes' in the sky as well, which is why there are lots of air traffic controllers at airports getting ulcers. Unless the current air traffic control model changes radically you are not going to have any flying cars at all, since it would require far too many air traffic controllers, and the complexity of handling 1 million flying cars at rush hour over large cities is going to be pretty bad.
Also, ever get delayed on landing or takeoff because your flight can't get a slot? Same thing will happen when everybody have flying cars since you wont be allowed to just land it anywhere.
And finally, if things get too congested at 100 feet, rise to 150 feet and go over it.
Um, maybe you should add a 0 or two to those numbers, I certainly wouldn't feel very safe travelling at over 250mph at 100 feet, or having things zipping by my office window at at those speeds.
Most likely you wont be allowed to fly your car yourself, it will all be flown by computers, and computers will do all the air traffic control. To develop and deploy such a complex system will take several decades IMHO. You probably have more of a chance of getting to the moon first, since that is just extrapolation of current working technology.
Doh! My bad, sorry.
CowboyNeal, please, why did you have involve the X-Prize in the post? The launch in November is not to try and win the X-Prize, and as far as I know they are not participating in the Ansari X-Prize at all. It's just another company getting in on putting payloads in space, and not even human payloads.
Thats probable what most of the crowd here would use.
Is it? Why would anybody use JDS when you have Debian (disclaimer: other dists are available)?
SunRay (at least the no-monitor version) is a super sweet piece of kit, it was my work desktop for a year and I loved it. Up until now it has just been a shame that you have to have Solaris installed to run it.
SunRay on Debian, yay! \o/
What is the proper way to behave when the world ends?
Don't Panic.
And always know where your towel is.
The earth curvature on this one shows just how close they got to space.
x /p hotos/images/video/for_dave.jpg
Right, so I guess they were just really really close to the ground on this one, as it curves the other way!
http://www.scaled.com/projects/tierone/New_Inde
Of course what you are really seeing is just wide/narrow angle lenses on the cameras being used, unless the earth shrank a lot while I wasn't looking.
An there I was going around believing that pollution was bad!
Hey ho, I guess we can all breathe easy now that we know that the next oil tanker going to the bottom or releasing CFC's into the atmosphere wont be a problem, because pollution has never been proven to be bad!
Are you kidding? Was this supposed to have been moderated Funny and not Insightful perhaps?
100 years is nothing! We have been using oil for about as long running our combustion engines, and we are running out, do you want the same thing to happen again to your grandchildrens children?
And burning coal is one of the worst pollutants there is, leading to acid rain, increased greenhouse effect, smog, etc. Or maybe you would like your kids to have to constantly puff on their asthma inhaler while hauling their decomposing personal belongings away from a flooded house in acid rain? Yeah, that sounds really good, especially since they managed to have enough food that long after all the billions others died from starvation when the crops failed.
I for one certainly look forward to living out my life in a dark acid wasteland.
crt (maker of Rocket Arena) posted on his site that Q3A only finds .dll's in the root Q3A directory.