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Comment Re:EC2 is scriptable (Score 3, Interesting) 80

The OP needs lower-priced spot instances, which are intermittently available and designed exactly for this workflow.

Here's how to utilize lower-priced spot instances for scientific computing:

1. Set up one long-running, low-cost instance (a small is fine) that creates a distributed queue using Amazon's SQS, and adds jobs to the queue corresponding to each "unit" of the relevant computational problem of interest. New jobs can be added using a command line interface, or through a web interface.

2. Create a user start-up Bash script for the spot instances that runs your main program -- I prefer using Python and boto for simplicity. The main program should connect to the SQS queue, and begin an "infinite" while loop. Inside the loop, the next job off the queue is pulled, containing the input parameters that define the "unit" of the computational problem of interest. These input parameters are fed to the main algorithm, and the resulting output is uploaded to Amazon S3. The loop continues.

3. Any time the queue is empty or the spot instance remains idle for ~5 minutes, the spot instance then auto-terminates using EC2's command line interface.

4. Finally, just write a simple Python script to pull all the results off S3, combine & analyze them, and export to another useful format.

You'll also need to set up your spot instance price threshold, and make sure the queue has jobs to run. That's it, it's fairly simple.

Comment That OO-My-God Moment of Emergence (Score 1) 242

Emergent OOism -- that everything is an object, including the variable types -- can provide continual surprises of what is possible, even to veteran programmers in other languages. As you were developing and using Python, Guido, what was your favorite surprise? What was now easily possible using Python that would have been very difficult with another language (at the time, or even nowadays)?

Mine: a dictionary of lambda functions for parsing text, and writing a custom MapReduce capability for AWS in 372 lines.

Security

Did the Spamhaus DDoS Really Slow Down Global Internet Access? 70

CowboyRobot writes "Despite the headlines, the big denial of service attack may not have slowed the Internet after all. The argument against the original claim include the fact that reports of Internet users seeing slowdowns came not from service providers, but the DDoS mitigation service CloudFlare, which signed up Spamhaus as a customer last week. Also, multiple service providers and Internet watchers have now publicly stated that while the DDoS attacks against Spamhaus could theoretically have led to slowdowns, they've seen no evidence that this occurred for general Internet users. And while some users may have noticed a slowdown, the undersea cable cuts discovered by Egyptian sailors had more of an impact than the DDoS."

Comment Re:Fortran is better. (Score 1) 793

I 100% agree.
And f2py is the perfect way to combine the advantages of Fortran + Python.
It beats SWIG any day.

I write lots of numerical codes for solving engineering problems, and most of the time I use Fortran, even though I have written some in C as well. Ultimately, the easier memory management and advanced array support is worth using a language considered by many to be strange and unusual. Of course, this is only for numerical analysis. Most other things I write in Python.

Medicine

Study Hints That Wi-Fi Near Testes Could Decrease Male Fertility 307

Pierre Bezukhov submits news of a report that "a laptop connected wirelessly to the internet on the lap near the testes may result in decreased male fertility," writing "'[The scientists who conducted the research] placed healthy sperms under a laptop running a Wi-Fi connection. After four hours, the Wi-Fi exposed sperms showed 'a significant decrease in progressive sperm motility and an increase in sperm DNA fragmentation' compared to healthy sperms stored for the same time in the same temperature away from the computer. That is, the sperms exposed to Wi-Fi were less capable of moving towards an egg to fertilize it and less capable of passing on the male's DNA if it does fertilize an egg.' The scientists blamed the damage on non-thermal electromagnetic radiation generated by the Wi-Fi." However, the experiment was based on sperm outside the body; the researchers (here's the abstract from their study) note that "Further in vitro and in vivo studies are needed to prove this contention."

Comment Road to Reality by Roger Penrose (Score 1) 358

The Road to Reality : A Complete Guide to the Laws of the Universe
by Roger Penrose
http://www.amazon.com/Road-Reality-Complete-Guide-Universe/dp/0679454438

Likely the most serious math book you will find in a retail, consumer bookstore. An excellent read and essential to truly understanding modern physics.

Displays

Why Are We Losing Vertical Pixels? 1140

An anonymous reader writes "Switching from 1600x1200 to wide 1680x1050 to HD 1600x900, we are losing more and more vertical space, thus it is becoming less and less simple to read a full A4 page or a web page or a function call. What's the solution for retaining the screen height we need to be productive?"
Star Wars Prequels

How Star Wars Trumped Star Trek For Scientific Accuracy 495

An anonymous reader writes "When George Lucas added the 'ring around the Death Star' effect to his 1997 re-release of Star Wars Episode IV: A New Hope, the revision was almost as hated as Greedo shooting first, and to boot was seen as a knock-off of the seminal 'Praxis effect' in Star Trek VI: The Undiscovered Country (1991). But a debunking astronomer claims that the Federation got it wrong and the fan-boys should thank Lucas for adding some scientific accuracy to his fictional universe."
Biotech

Florida Lab Gets Pregnant 149

Synthetic Biology, a relatively new field, is seeking to find out what happened to a bunch of chemicals to make them capable of supporting a metabolism, replicating, and evolution. A Florida lab is showing some of the most promising advancements in this direction with their AEGIS (Artificially Expanded Genetic Information System) experiment. "AEGIS is not self-sustaining, at least not yet, and with 12 DNA building blocks -- as opposed to the usual four -- there's little chance it will be confused with natural life. Still, Benner is encouraged by the results. 'It's evolving. It's doing what we designed it to do,' said Benner, a biochemist with the Gainesville, Fla.-based Foundation for Applied Molecular Evolution. In addition to providing an example of how alien life might be cobbled together, synthetic biology has a broad array of uses on the home front."
Data Storage

Submission + - One Terabyte DVD

MindlessPhilosophy writes: "A research team at the University of Central Florida led by Kevin Belfield has recently made a major breakthrough in Data Storage and Photonics with the development of a one terabyte DVD (Central Florida Future). From the article: 'While initial applications for the DVD will likely be for the military, large corporations and the medical field, Belfield is also excited about the possibility of consumer applications — especially in the gaming industry.'"
Privacy

Social Network Users Have Ruined Their Privacy 308

Steve Kerrison writes "'There's little point in worrying about ID cards, RFID tags and spyware when more and more people are throwing away their privacy anyway. And the potential consequences are dire.' I've written an article on the dangers of social networks and how many users seem to forget just how public the information they post can be. This follows a warning sent out by the CS department of Bristol University, advising students that they risk lost job opportunities, getting in trouble with their parents and more, if they don't take care. The warning, however, really applies to all social network users, be they college students or over-zealous blog posters."

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