I am surprised how they manage to get scala to perform so much worse than pure java.
Scala does generate optimized Java byte code. Pretty much any Java code can be directly ported to Scala with nearly identical performance.
The Scala benchmarks perform worsethan Java's, on average, for two main reasons. The first is that some of the tasks have been implemented using higher level code (think memory allocation and closure generation), trading conciseness for performance. The second is that the Scala benchmarks haven't been tuned and tweaked to the extent that the Java ones have.
Then there are a couple benchmarks where Scala's performance is hugely worse than Java. This seems to be because the Java benchmark was implemented using optimized native libraries (big integers as I recall) or using a better algorithm. Again, Scala could achieve equivalent performance in principle, but someone needs to invest the time to update the benchmark implementations.
For people like me, without Scala the JVM wouldn't even be under consideration, though I admit that Java has been more usable since it got generics.
The creator of Scala, Martin Odersky, was instrumental in the design and development of Java's generics. I believe he is also responsible for (some version of) Sun's javac implementation.
In my opinion, Scala is excellent. So far I've used Scala to generate code which leverages NVIDIA GPU's for computational physics. I've also used Scala to do simple combinatorics and text processing. The latter is particularly pleasant -- a parser-combinator framework is included in the standard library which makes it a snap to define and process arbritrary grammars. My biggest frustration with Scala has been the somewhat spotty IDE support (compared to Java). However, the situation is improving and decent plugins for Eclipse, Netbeans and IDEA are all on the horizon.
For those not familiar, let me give a short advertisement for Zotero. I'm a Mac user, and I recently switched from Safari to Firefox just for Zotero. Zotero makes it possible to add a citation entry to my library with one click in Firefox. Another nice feature is Zotero's ability to determine citation information for loose PDF's. And did I mention that Zotero is free?
As I remember, the NeXT computers (think original OS X) were also very expensive when they were released. According to Wikipedia, about $10,000 in 1990.
I'm currently using Texmacs to type in my math. Entering greek characters and structured expressions is a breeze. For example, to get \alpha^2 you'd enter the following keystrokes: [a] [tab] [^] 2
Texmacs is WYSIWYG, like a word processor, so you only see the typeset document, and not the underlying text file.
There are disadvantages though; for publication, I have to make use of Texmacs "export to Latex" feature, which does not provide an optimal Latex file. It is also not possible (I believe) to import a Latex file. And Latex is the lingua franca of scientific writing. Texmacs also seems to have a small user base.
Nonetheless, Texmacs is the fastest and most efficient tool I have found for math heavy writing.
This is incorrect as stated. Photons don't have rest mass, but they DO have energy and momentum. It is the energy and momentum which couple to gravity, so that photons do interact gravitationally.
Actually, I just took a class in Nuclear Engineering, we concentrated a lot on the public's fear of nuclear facilities. The public is completely ill-informed when it comes to anything nuclear. People fear that waste will get spread around-the waste is stored in steel containers that can survive a train hitting them plus being doused in jet fuel and lit on fire (I saw a film of it.) ...
Hmm, I was a student at Los Alamos last semester, and I got a different impression. Apparently in certain areas of Los Alamos, there are these humongous underground concrete enclosures, containing these metal canisters, containing nuclear waste back from the early days. Furthermore, it's just a matter of time before the waste seaps out (unless some repackaging is eventually done); it's already eating through the metal. I think this stuff lasts for a very long time.
There are scientists at Los Alamos studying hydrology with the intent of making sure that any waste which does escape does not get into the water supply, before something else can be done about it.
Anyone who works near any radiation must wear geiger counters, which are checked monthly. So, probably no one is getting cancer yet, but it certainly doesn't feel very green to me.
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I am surprised how they manage to get scala to perform so much worse than pure java.
Scala does generate optimized Java byte code. Pretty much any Java code can be directly ported to Scala with nearly identical performance.
The Scala benchmarks perform worsethan Java's, on average, for two main reasons. The first is that some of the tasks have been implemented using higher level code (think memory allocation and closure generation), trading conciseness for performance. The second is that the Scala benchmarks haven't been tuned and tweaked to the extent that the Java ones have.
Then there are a couple benchmarks where Scala's performance is hugely worse than Java. This seems to be because the Java benchmark was implemented using optimized native libraries (big integers as I recall) or using a better algorithm. Again, Scala could achieve equivalent performance in principle, but someone needs to invest the time to update the benchmark implementations.
Life on earth exhibits a specific "handedness" or chirality. All DNA twists the same way, for example. Apparently the term for this is homochirality.
http://en.wikipedia.org/wiki/Homochirality
For people like me, without Scala the JVM wouldn't even be under consideration, though I admit that Java has been more usable since it got generics.
The creator of Scala, Martin Odersky, was instrumental in the design and development of Java's generics. I believe he is also responsible for (some version of) Sun's javac implementation.
For a reference, see
http://www.artima.com/forums/flat.jsp?forum=276&thread=221233
In my opinion, Scala is excellent. So far I've used Scala to generate code which leverages NVIDIA GPU's for computational physics. I've also used Scala to do simple combinatorics and text processing. The latter is particularly pleasant -- a parser-combinator framework is included in the standard library which makes it a snap to define and process arbritrary grammars. My biggest frustration with Scala has been the somewhat spotty IDE support (compared to Java). However, the situation is improving and decent plugins for Eclipse, Netbeans and IDEA are all on the horizon.
It seems like this method requires jailbreaking. Here's another reference.
My main issue with it is that there's no method of syncing or consolidating and index or database between multiple comps.
There is a Zotero beta available which does provide synchronization support (its called 1.5 sync preview, available here http://www.zotero.org/documentation/sync_preview.)
For those not familiar, let me give a short advertisement for Zotero. I'm a Mac user, and I recently switched from Safari to Firefox just for Zotero. Zotero makes it possible to add a citation entry to my library with one click in Firefox. Another nice feature is Zotero's ability to determine citation information for loose PDF's. And did I mention that Zotero is free?
As I remember, the NeXT computers (think original OS X) were also very expensive when they were released. According to Wikipedia, about $10,000 in 1990.
I'm currently using Texmacs to type in my math. Entering greek characters and structured expressions is a breeze. For example, to get \alpha^2 you'd enter the following keystrokes:
[a] [tab] [^] 2
Texmacs is WYSIWYG, like a word processor, so you only see the typeset document, and not the underlying text file.
There are disadvantages though; for publication, I have to make use of Texmacs "export to Latex" feature, which does not provide an optimal Latex file. It is also not possible (I believe) to import a Latex file. And Latex is the lingua franca of scientific writing. Texmacs also seems to have a small user base.
Nonetheless, Texmacs is the fastest and most efficient tool I have found for math heavy writing.
This is incorrect as stated. Photons don't have rest mass, but they DO have energy and momentum. It is the energy and momentum which couple to gravity, so that photons do interact gravitationally.
A good reference is here:
http://math.ucr.edu/home/baez/physics/Relativity/SR/light_mass.html
Actually, I just took a class in Nuclear Engineering, we concentrated a lot on the public's fear of nuclear facilities. The public is completely ill-informed when it comes to anything nuclear. People fear that waste will get spread around-the waste is stored in steel containers that can survive a train hitting them plus being doused in jet fuel and lit on fire (I saw a film of it.) ...
Hmm, I was a student at Los Alamos last semester, and I got a different impression. Apparently in certain areas of Los Alamos, there are these humongous underground concrete enclosures, containing these metal canisters, containing nuclear waste back from the early days. Furthermore, it's just a matter of time before the waste seaps out (unless some repackaging is eventually done); it's already eating through the metal. I think this stuff lasts for a very long time.
There are scientists at Los Alamos studying hydrology with the intent of making sure that any waste which does escape does not get into the water supply, before something else can be done about it.
Anyone who works near any radiation must wear geiger counters, which are checked monthly. So, probably no one is getting cancer yet, but it certainly doesn't feel very green to me.
kipton