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Comment Re:Better Than First Edition? (Score 1) 163

I sincerely hope that this version is better than the first edition, although anything short of a random re-arrangement of pages would serve as an improvement. The first edition actually delayed my initial use of Python by about a year and a half. I had heard wonderful things about the language so I figured, "Ah, an O'Reilly book!" Big mistake.

Wow, I'm quite surprised actually, I had exactly the opposite experience with the first edition of "Learning Python."

I distinctly remember picking up the book in '99, reading the first three chapters to get introduced to the language basics, then writing my first web-scraper to pull weather forecasts off and forward them as emails, arriving on my handset as an SMS message (AT&T was running a free email-to-SMS gateway at the time, and didn't charge to receive the messages). I think I skipped ahead to chapter 11 or so to find the code for reading html as text from a URL, as opposed to a local file.

I had never written a tool which perform network lookups and was really impressed with the simplicity of the language and the book. The progression was from the very general to the very specific. The first three chapters were a history and basic introduction to the relatively unique concepts such as whitespace handling and how to deal with strings, as well as how Python handles common stuff like while and for loops. If I recall correctly it stepped into classes and objects after that, then proceed into specific libraries.

I've been doing professional coding in Python ever since, and always recommend "Learning Python" as an introduction to newbies.

My only disappointment in fact was that the size of the book has grown so much in the course of the last few editions.

Comment Hardware Specs (Score 4, Informative) 44

The hardware specifications alone are pretty impressive:

Computation The PR2 robot has two eight-core i7 Xeon system servers on-board, each with 24 GB of RAM, a 500 GB internal hard drive, and a 1.5 TB external removable log drive. The computers and most of the sensors communicate over a 16-port gigabit Ethernet hub with a 32-gigabit backplane. The robot also has an on-board, dual-radio router that can be bridged into a WLAN, as well as a secondary, stand-alone access point for laptop or smart phone access.


The PR2 ships with sensors in the head, arms, and base. The head contains two stereo camera pairs coupled with an LED pattern projector, a 5MP camera, a tilting laser range finder, and an IMU. The forearms each contain an ethernet-based, wide-angle camera, while the grippers have three-axis accelerometers and pressure sensor arrays on the fingertips. The base has a fixed laser range finder.

That's a fair bit of grunt to throw at the OpenCV libraries, which is listed under their Supported Projects in the Software section. No surprise either, Willow Garage has taken over hosting the project from Intel.

Comment enemy territory (Score 2, Informative) 460

I've not really played PC games since the Doom era so I'm really out of touch here. I don't have a real gamer box, just a simple video card. What do Slashdotters think I should try? A simple FPS or some type of networked game would do.

Sounds like you've missed a fair few generations of games then.

Try giving Enemy Territory a go.

Quite addictive in its time and a nice cooperative element to online play.

It was released back in 2003, and runs quite well on Linux. You did mention only having a "simple" video card but odds are better than even your system has sufficient support - even basic integrated video chipsets tend to have some degree of OpenGL support these day.

System requirements are: 600 MHz CPU, 128 MB RAM, 32 MB OpenGL graphics card, 56.6k Modem/LAN

Its not quite Open Source but it is (and always has been) free as in beer.


Submission + - Convincing your company to go Open Source 1

Cycon writes: "No doubt asked previously, but what are today's most compelling arguments (pro or con) for a small company to release its software under an Open Source license, in particular the GPL? Current and future fund raising may be jeopardized or at least complicated. There may be fears competitors will more easily absorb your unique features, or a larger entity will leverage your work and push you aside. On the positive side is ethical merit — which beyond as its own end may offer community benefits such as code contributions, constructive testing and feedback, and perhaps some good press. Lawyers may be required for the finer points, but what should any realistic business consider?"

Comment Re:Intel counters with CPU+GPU on a chip (Score 1) 176

Microsoft wouldn't allow licensing dual cores on netbooks.

As far as I can tell, that's only regards Windows XP.

See this article (which, admittedly, its talking about a "nettop" box, not a netbook:

...first thing you see is that it runs on Windows Vista - XP under Microsoft's licensing terms for netbooks limited it to single core CPUs.

Got anything which specifically states that other OS's besides XP (which they've been trying to drop support on for a some time now) is restricted regards Dual Core?

Comment Re:Indefinitely (Score 1) 575

Hearing implants are apparently already pretty good. They went from "hear something" to "hear people talk but bit wonky" in a decade or so. The obvious huge difference here is that the implants are connected to I/O already present in the brain wetware and it's still extremely difficult to pull off. Your calculator example would require completely artificial interface layer to the brain ... Subvocalizing would be relatively straightforward to do, thought. You could have conversation with your implants hooked to your auditory nerve.

I'm assuming by "subvocalizing" you mean effecting speech without actually using the human voicebox, then transferring that speech information electronically to a "receiver" which is hooked up to a hearing implant?

So why can't I subvocalize "Computer, what's 63 * 14.69", pass through speech recognition, process the result, and transmit back to my own hearing implant?

In the long term, surely any "interface layer to the brain" would ultimately have to enter human consciousness in order to be perceived anyway. I don't think a wet-wired calculator would cause an imaginary physical calculator to suddenly appear into anyone's head - one needs a mental model for interacting with device. Speech and hearing seems an ideal, or at least achievable goal.

The next step would be to actually be to process an manipulate the visual stream between the eyes and the brain. Perhaps you could "draw" a calculator over someone's visual field, heads-up-display style. I would expect the level of precision and bandwidth would remain out of reach for our lifetimes however, and even then you still need a means of "pressing" the buttons.

Much more likely, easier, safer and possibly effective to display onto glasses - in which case the audio component can be built into headphones at the end of the glasses, and a direction mic could pick up whispering. Why tap into the brain at all? (c:

Comment Re:I want to see 'battery drop off centers' (Score 1) 369

the idea I would LOVE to see is where there are frequent stops (like gas stations) where you can swap your drained batt for a freshly charged one. they have that idea for propane tanks at supermarkets - you don't have to WAIT to have yours filled; you simply swap your empty for a full one.

The short answer to your question is the way any given battery is treated over the course of its usage has a drastic effect on the battery's ability to build and maintain a charge.

I've recently performed a complete electrics overhaul on a yacht, complete with solar panels, regulators, meters to measure amp input and output, etc. The goal was to build a system capable of powering a laptop (netbook actually) and a mobile phone using a constant 3G connection for 8-10 hours per day entirely off solar and the occasional (once every 3-4 days) 30-60 minute idle generation from the engine to make up the difference.

Without getting too far into technical details, you really only ever get to use 35% of a battery's rated capacity. At that point you need to recharge it or you risk permanent damage. You need pretty complex gear even to monitor how much energy you are using at a given time. For example, as you discharge a battery its voltage drops. But it doesn't do it immediately. You would have to wait approximately 24 hours after using a battery before a simple voltmeter would give you an accurate reading.

Bottom line, if you take a normal 12V car battery and wind it down to below 10.5 volts or so, you're effectively eliminated 50% of the battery's capacity on future charges. Do it a couple times and your car might start once or twice more, then probably never again.

The types of batteries used in these applications are many grades higher than the engine starting battery in your car right now of course, but the problems from repeatedly over-discharging still apply.

Are you willing to trust the person who had the battery in your car last to have treated it as well as you would have?

Comment Re:Squid. (Score 1) 450

Judging by my squid analysis (using Calamaris), Squid will only save about 10% of a small network's bandwidth -- even if it is setup with a reasonably large (5GB) cache and a large size (100MB) for the maximum size of cached objects.

When tethering via mobile data plan (where I also happen to have a 1 GB/mo cap), I frequently connect to my office computer via compressed SSH tunnel, using a port redirect to a squid cache server running there, eg:

ssh user@workstation -C -L 3128:localhost:3128

Then I set up a second squid caching server on my laptop, which itself connects to the first proxy via the compressed tunnel.

SSH adds some overhead in exchange for the security, but I find the compression on the link more than makes up for it, especially with large HTML and other text files. The only point of the remote caching proxy is to act as a gateway for the local one (the caching feature being secondary). If the page is in the cache, I don't end up downloading it a second time, and if not I get "free" compression (c:


Submission + - Favourite Predictive Science Fiction?

Cycon writes: "William Gibson's 1984 novel Neuromancer popularized the term cyberspace, and predicted as much as influenced directions taken by the modern internet (and of course much of the plot and setting of The Matrix was lifted directly). Neil Stephenson's Snow Crash in 1992 has arguably led to everything from use of the word "avatar" to MMOs such as Second Life and interfaces such as Google Earth. Many space-related ideas explored by Arthur C. Clark's such as a Space Needle are being actively investigated, and one can find many parallels between Star Trek's tricorder and communication and modern smart phones.

What other favourite authors or works can the Slashdot community recommend which stand as not only great writing, but as examples of ideas or concepts which were later developed, or could realistically be produced in the next twenty years?"

Submission + - New Android SDK Available, Phones Predicted Nov 10 (

Cycon writes: "Google has announced, "we're releasing a beta SDK. You can read about the new Android 0.9 SDK beta at the Android Developers' Site, or if you want to get straight to the bits, you can visit the download page." A new Development Roadmap has also been released to help developers understand the direction the software is taking (as this is still only a Beta release).

In addtiona the FCC has approved the HTC Dream, and it is believed Google will launch the phone on November 10, since a confidentiality request attached to the application asks the FCC to keep details secret until that date."


Submission + - Lucas Researching Concept for New Indianna Jones (

Cycon writes: "According to George Lucas, "The franchise really depends on me coming up with a good idea," Lucas said. "And that series is very research-intensive. So we're doing research now to see if we can't come up with another object for him to chase ... hopefully we'll come up with something." Lucas "scoffed at the possibility of passing the famed fedora from Ford to Shia LaBeouf" instead stating "if [Harrison Ford] wasn't in it, you'd have to call it 'Mutt Williams and the search for Elvis.'"
Red Hat Software

Submission + - Fedora 8 Released (

Cycon writes: "Fedora 8 has been released. New features include PulseAudio, Codec Buddy, Compiz-Fushion, integrated Mugshot and Bigboard, IcedTea, and more. Take an online tour of the latest in line of Red Hat's community Linux distribution or download via torrent here."
Portables (Apple)

Submission + - Apple slashes iPhone to $400, Drops 4GB, & Ref

Cycon writes: "Apple has announced they will be dropping the price of the 8GB iPhone to $399 (plus contract), will be dropping the 4GB model, and in response to frustration from early-adopters, and will offer a refund in the form of $100 store credit to early adopters. "Our earlier customers trusted us and we must live up to that trust with our actions in moments like this," says Steve Jobs."

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