I maintain that your information is out of date. Java will exceed the speed of a C++ program in many cases nowadays.
I agree, memory allocation can be faster, and the VM can compile the code to use all available features on the target processor. I doubt that the compiler can perform as many and thorough optimizations as a static compiler though.
I worked for a large insurance company and we had to prove to them using benchmarks that Java was faster. We won and that company now only uses Java.
I'm sure that using different implementations would have given different results.
You're avoiding the issues of real-world development also. What is the expense of a memory leak? You can claim that they also can exist in Java but as we all know in C++ they are a constant problem--especially for the newbie programmers. So, are you putting this forward as an advantage of C++? I see the dangers to the inexperienced programmer as being much higher in C++ than in Java. What's your point? Are you proud that it's so easy to create a memory leak in C++?
It's a common misunderstanding that garbage collection prevents memory leaks. It doesn't, it prevents use of dangling pointers. In C++ you can either create a memory leak (by not calling delete) or create a dangling pointer (by calling delete but leaving references to the deleted object). The former is always a bug, the latter only if you dereference the pointer (after which you usually crash or corrupt data). In Java, you can create a memory leak (by having references to unneeded objects in live objects), but you can't create a dangling pointer. You can accidentally use an object which is supposed to unneeded though (causing a violation of program invariants / contracts, without a crash but possibly corrupting data).
However, it is possible to "sharpen" blurred images, if you have more than one (differently) blurred image of the same object. Then each blurred image contains different information, and with suitable assumptions about the blurring mechanism you can reconstruct a sharper image.
I had to do this at school a couple of years ago, and it seems they still give the same assignment: http://www.cis.hut.fi/Opinnot/T-61.5040/Htyo2006/o mm06_project.pdf . The idea is to construct a Bayesian model, and feed several blurred images to it. The model assumes that blurring works so that each blurred pixel is a weighted average of the high-resolution pixels surrounding the center of the blurred pixel, and some white noise of course. Obviously the exercise is quite elementary, but the idea is solid.
If we were really, really optimistic about CSI, maybe the surveillance cameras have a low resolution, but a high framerate, and the criminals/cars/whatever typically stand still for long periods of time. Then it would actually be possible to do what they do!:)
Did they classify the non-drinkers to those not drinking because they've chosen so, and to those not drinking because of an illness (think exploded liver or pancreas)? There was a news item earlier this year, in which they had noticed that some similar studies had not.
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If I have understood correctly, http://www.mozilla.org/projects/tamarin/ and related projects will be a big win for JavaScript performance.
I agree, memory allocation can be faster, and the VM can compile the code to use all available features on the target processor. I doubt that the compiler can perform as many and thorough optimizations as a static compiler though.
I worked for a large insurance company and we had to prove to them using benchmarks that Java was faster. We won and that company now only uses Java.I'm sure that using different implementations would have given different results.
You're avoiding the issues of real-world development also. What is the expense of a memory leak? You can claim that they also can exist in Java but as we all know in C++ they are a constant problem--especially for the newbie programmers. So, are you putting this forward as an advantage of C++? I see the dangers to the inexperienced programmer as being much higher in C++ than in Java. What's your point? Are you proud that it's so easy to create a memory leak in C++?It's a common misunderstanding that garbage collection prevents memory leaks. It doesn't, it prevents use of dangling pointers. In C++ you can either create a memory leak (by not calling delete) or create a dangling pointer (by calling delete but leaving references to the deleted object). The former is always a bug, the latter only if you dereference the pointer (after which you usually crash or corrupt data). In Java, you can create a memory leak (by having references to unneeded objects in live objects), but you can't create a dangling pointer. You can accidentally use an object which is supposed to unneeded though (causing a violation of program invariants / contracts, without a crash but possibly corrupting data).
See e.g. http://www.ibm.com/developerworks/java/library/j-l eaks/ for more information.
I agree that it's hilarious, every time.
However, it is possible to "sharpen" blurred images, if you have more than one (differently) blurred image of the same object. Then each blurred image contains different information, and with suitable assumptions about the blurring mechanism you can reconstruct a sharper image.
I had to do this at school a couple of years ago, and it seems they still give the same assignment: http://www.cis.hut.fi/Opinnot/T-61.5040/Htyo2006/o mm06_project.pdf . The idea is to construct a Bayesian model, and feed several blurred images to it. The model assumes that blurring works so that each blurred pixel is a weighted average of the high-resolution pixels surrounding the center of the blurred pixel, and some white noise of course. Obviously the exercise is quite elementary, but the idea is solid.
If we were really, really optimistic about CSI, maybe the surveillance cameras have a low resolution, but a high framerate, and the criminals/cars/whatever typically stand still for long periods of time. Then it would actually be possible to do what they do! :)
Did they classify the non-drinkers to those not drinking because they've chosen so, and to those not drinking because of an illness (think exploded liver or pancreas)? There was a news item earlier this year, in which they had noticed that some similar studies had not.