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Comment Re:Please correct me if I'm wrong.... (Score 1) 99

The question here is.... where is the pressure on Mars at 10 millibars? At the bottom of Hellas Basin and Valles Marineris it can certainly approach a couple hundred millibar of pressure.

At the bottom of Hellas Basin, air pressure is 11.5 millibars. You might want to consider the saying that "when you're in a hole (e.g., the Hellas Basin), you need to stop digging."

Comment Re:Please correct me if I'm wrong.... (Score 2, Informative) 99

As for Total Recall, I thought it was a fun diversion, but as for realism I thought it was absolutely stupid and highly inaccurate. "Scientifically accurate depiction of exposure to the Martian atmosphere".... hardly. It looked cool on film I suppose but it really didn't work very well. FYI, you can survive on Mars with mostly a pressure suit and an oxygen mask. Parts of the surface of Mars have the same atmospheric pressure as the top of Everest. Really, it isn't nearly as bad as depicted in the movie.

Your complaints about the movie's scientific accuracy would be more compelling if you were more accurate than the movie was. Air pressure on Mars is less than 10 millibars. Air pressure at the top of Mt. Everest is about 300 millibars. Not remotely "the same atmospheric pressure".

Comment It's slipping already (Score 1) 356

The summary quotes the last paragraph of the article as saying

The game is currently expected to ship in 2010 although given its history Pitchford is understandably reluctant to be more specific.

but now the article says

The game is currently expected to ship in 2011 although given its history Pitchford is understandably reluctant to be more specific.

Comment Re:Objects... (Score 1) 237

If you learn about C++ before you try to pass yourself off as an authority, you won't spout easily refutable misconceptions.

C++ only becomes slower if you use certain features that have a performance impact.

And virtually every useful feature of C++ that is not in its common subset with C is one of those.

What is the performance overhead of namespaces, typesafe object creation, references, function and operator overloading, use of const ints for array sizes (more efficient than C), non-virtual methods, STL (the word "virtual" does not appear anywhere in the STL sources), support for wide characters, protected/private modifiers, etc.? While features like templates and metaprogramming have performance tradeoffs, skilled programmers can use them to make programs that are faster than the corresponding C programs.

Example: if you use exceptions, there is a performance penalty.

And if you use operator new, you use exceptions.

Firstly, this whole point is spurious because you can always use nothrow new, which was put in the standard precisely for people who want exception-free code.

Secondly, the (exception-throwing version of) new may well be faster at error handling than malloc. For the very many programs that only catch allocation errors at the top level, setting up the exception handler is just negligible part of startup costs and far faster than checking the return value from each malloc for zero.

Even if you are doing fine-grained error checking around each call to new, it's not clear whether setting up the exception handler is slower than checking for a null-returrn. It is certainly far less error-prone.

The main slow downs you will see in your average C++ program, over the corresponding C, is the use of the string class

That and <iostream>. Once, I tried programming in GNU C++ for a system with an ARM7 CPU and 288 KiB of RAM. Even after applying all the link-time space optimizations I could find, Hello World statically linked against GNU libstdc++'s <iostream> still took 180 KiB. (Dynamic linking wouldn't even have worked because libstdc++.so itself is bigger than RAM.)

Many C++ programmers use printf instead of iostream. You're perfectly free to use whichever you want, depending whether you are more concerned with code size/performance or type-safety/extensibility.

Note that C++0x has features specifically designed to support a typesafe printf, which will completely own the very type-unsafe C version.

Furthermore, C++ templates allow code re-use with exactly 0 performance loss

As I understand it, C++ compilers implement templates by making a copy of the object code for each type for which the template code is instantiated. Once you instantiate a template numerous times, your binary gets bigger, and it slows down because it has to keep loading data from storage instead of caching it in RAM. This hurts especially on handheld platforms such as the Nintendo DS, which has only 4 MiB of RAM.

I agree that Nintendo DS programmers should limit their use of templates. Not sure why the many programs which are not targeted at the Nintendo DS (Even the DSi has 4 times as much memory) shouldn't be able to generate the far-faster code made possible by template programming (See the "Was it Worth It?" section here).

Frankly, there is no valid reason for starting a new program in C in this day and age.

This is true but only technically, because most of C is also contained in C++.

I think you'd have to have a paltry imagination and poor grasp of the many powerful techniques possible in C++ not to use any C++-specific features.

Comment Lists of conference rankings and how to use them (Score 1) 279

http://www.cs.albany.edu/~ashwin/Conf_rank.html
http://libra.msra.cn/conf_category_1.htm
http://www.cs-conference-ranking.org/conferencerankings/topicsiv.html

The common procedure is to first submit to the most prestigious conference in the appropriate specialization that you think might accept your paper. A good way to guesstimate this is by looking at past papers from the conference. Even if you aren't an ACM or IEEE member (and you should probably join if you can afford it), you can browse the abstracts at the ACM and IEEE portals, which should be good enough for your purposes. You'll also want to look at the related papers in preparing your own paper's list of references (nearly all papers compare explicitly to previous research and state what the innovation over the current research status is in the paper).

If they accept your paper, great. If not, they'll usually send you the reviewer's comments. Next, use these comments to make your paper better and submit it to the next best conference that you think might accept your paper. Repeat until accepted.

This procedure will definitely work because eventually you'll get to low prestige journals that should accept pretty much anything that's not simply incorrect. Don't feel bad if this happens. Many papers subsequently recognized as important had to be shopped into obscure journals, so even this worst-case scenario is not that bad.

Good luck!

Comment Re:Everyone gets to be an astronaut fireman rock s (Score 2, Informative) 1138

The robots idea isn't far from the truth. The value of goods manufactured in the US has actually grown during the past decade (no "poor foreigners" involved) while manufacturing employment has gone way down. That is the result of increased productivity. While manufacturing may come back strong in the US, manufacturing employment won't. There are a lot of things that need to be done, but they many of them require strong educational background and 21st century skills.

Comment Re:Everyone gets to be an astronaut fireman rock s (Score 2, Informative) 1138

Nice way to hide misrepresentation of the facts with an emotional appeal. The actual facts are that 4.5 million construction and manufacturing jobs have been lost this decade (~20% of the total). Jobs that don't require higher education are declining (this is spelled out in a lot more detail at the link). While I have no disrespect for the guy who washes dishes, there are a lot more people who are willing and able to wash dishes than dishwashing jobs. We're not doing anyone a favor by not educating our population for the jobs that we will require.

Comment That's not what the statistics say (Score 1) 1138

FiveThirtyEight looked at this question from a fairly rigorous statistical point of view. Their conclusion was that college graduates have far better career prospects than lower levels of educational achievement. In fact, US college graduates have remained at (the technical definition of) full employment throughout the current economic downturn, while other groups have suffered terribly. The obvious conclusion is that there are not too many college graduates.

Comment If you include statistics, the answer is "yes" (Score 1) 609

I got a Ph.D. minus epsilon in Math, but never took a statistics course prior to dropping out during the dotcom boom to start a software company. I would trade most of the math I know (which I rarely use) for a solid background in statistics, which comes up all over the place, from the performance of data structures and algorithms, to dataflow analysis, to mining databases, to projecting performance failure rates, etc. This is not just basic statistics (which I managed to pick up on the street), but a deep knowledge of statistics can make a big difference. I just co-authored a paper on a very simple data structure for which the key step in analyzing its performance is to apply the Kolmogorov-Smirnov distribution.

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