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Comment People can't buy what they don't know exists (Score 2) 65

its not like there are not already 100's of them out there

That depends on whether home users are aware that these "already 100's of them" exist. A lot of them are sold only online, not in brick-and-mortar stores where one is already shopping for other things, and they aren't promoted very well. Google can back the Chromecast with marketing muscle in Latin-alphabet markets that a no-name Chinese company can't really match.

Comment Software freedom, user freedom, developer freedom (Score 1) 63

Copyleft makes sure that users retain freedoms, including the freedom to hire developers to make the software do what the user wants.

No, copyleft puts software first, and the user second.

How is that the case? A free software license guarantees four freedoms to the users of a work. Because the work is free, all of its users are free, even if this is freedom is at the expense of some developers' business models.

Without strong copyright laws, something like GPL is totally impossible.

Without software copyright, anybody can obtain a copy of a proprietary program and lawfully disassemble, document, and distribute it.

Submission + - Same programs + Different computers = Different weather forecasts (ametsoc.org)

knorthern knight writes: Most major weather services (US NWS, Britain's Met Office, etc) have their own supercomputers, and their own weather models. But there are some models which are used globally. A new paper has been published, comparing outputs from one such program on different machines around the world. Apparently, the same code, running on different machines, can produce different outputs due to accumulation of differing round-off errors. The handling of floating-point numbers in computing is a field in its own right http://docs.oracle.com/cd/E19957-01/806-3568/ncg_goldberg.html

The paper apparently deals with 10-day weather forecasts. Weather forecasts are generally done in steps of 1 hour. I.e. the output from hour 1 is used as the starting condition for the hour 2 forecast. The output from hour 2 is used as the starting condition for hour 3, etc.

The paper is paywalled, but the abstract at http://journals.ametsoc.org/doi/abs/10.1175/MWR-D-12-00352.1 says...

The global model program (GMP) of the Global/Regional Integrated Model system (GRIMs) is tested on 10 different computer systems having different central processing unit (CPU) architectures or compilers. There exist differences in the results for different compilers, parallel libraries, and optimization levels, primarily due to the treatment of rounding errors by the different software systems. The system dependency, which is the standard deviation of the 500-hPa geopotential height averaged over the globe, increases with time. However, its fractional tendency, which is the change of the standard deviation relative to the value itself, remains nearly zero with time. In a seasonal prediction framework, the ensemble spread due to the differences in software system is comparable to the ensemble spread due to the differences in initial conditions that is used for the traditional ensemble forecasting.

Comment DVD for areas without cable or DSL (Score 3, Informative) 176

Digital Versatile Disc is a cost-efficient medium for moving 4 to 8 GB packets of data in and out of geographic areas not served by a wired broadband provider. Cellular ISPs in the United States charge on the order of $10 per GB for microwave data transmission; satellite ISPs aren't much cheaper.

Comment Song of the South (Score 2) 176

A streaming service with every film ever produced is not likely in either of our lifetimes. For one thing, it'd have to include Song of the South, and Disney has made it clear by its actions over the past two decades that it doesn't plan to release that film as part of its standard "vault" rotation.

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