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Donald Knuth Turns 80, Seeks Problem-Solvers For TAOCP
 
An anonymous reader writes: When 24-year-old Donald Knuth began writing The Art of Computer Programming, he had no idea that he'd still be working on it 56 years later. This month he also celebrated his 80th birthday in Sweden with the world premier of Knuth's Fantasia Apocalyptica, a multimedia work for pipe organ and video based on the bible's Book of Revelations, which Knuth describes as "50 years in the making." But Knuth also points to the recent publication of "one of the most important sections of The Art of Computer Programming" in preliminary paperback form: Volume 4, Fascicle 6: Satisfiability. ("Given a Boolean function, can its variables be set to at least one pattern of 0s and 1 that will make the function true?") Here's an excerpt from its back cover: Revolutionary methods for solving such problems emerged at the beginning of the twenty-first century, and they've led to game-changing applications in industry. These so-called "SAT solvers" can now routinely find solutions to practical problems that involve millions of variables and were thought until very recently to be hopelessly difficult. "in several noteworthy cases, nobody has yet pointed out any errors..." Knuth writes on his site, adding "I fear that the most probable hypothesis is that nobody has been sufficiently motivated to check these things out carefully as yet." He's uncomfortable printing a hardcover edition that hasn't been fully vetted, and "I would like to enter here a plea for some readers to tell me explicitly, 'Dear Don, I have read exercise N and its answer very carefully, and I believe that it is 100% correct,'" where N is one of the exercises listed on his web site. Elsewhere he writes that two "pre-fascicles" -- 5a and 5B -- are also available for alpha-testing. "I've put them online primarily so that experts in the field can check the contents before I inflict them on a wider audience. But if you want to help debug them, please go right ahead."

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Has the Decades-Old Floating Point Error Problem Been Solved?
 
overheardinpdx quotes HPCwire: Wednesday a company called Bounded Floating Point announced a "breakthrough patent in processor design, which allows representation of real numbers accurate to the last digit for the first time in computer history. This bounded floating point system is a game changer for the computing industry, particularly for computationally intensive functions such as weather prediction, GPS, and autonomous vehicles," said the inventor, Alan Jorgensen, PhD. "By using this system, it is possible to guarantee that the display of floating point values is accurate to plus or minus one in the last digit..." The innovative bounded floating point system computes two limits (or bounds) that contain the represented real number. These bounds are carried through successive calculations. When the calculated result is no longer sufficiently accurate the result is so marked, as are all further calculations made using that value. It is fail-safe and performs in real time. Jorgensen is described as a cyber bounty hunter and part time instructor at the University of Nevada, Las Vegas teaching computer science to non-computer science students. In November he received US Patent number 9,817,662 -- "Apparatus for calculating and retaining a bound on error during floating point operations and methods thereof." But in a followup, HPCwire reports: After this article was published, a number of readers raised concerns about the originality of Jorgensen's techniques, noting the existence of prior art going back years. Specifically, there is precedent in John Gustafson's work on unums and interval arithmetic both at Sun and in his 2015 book, The End of Error, which was published 19 months before Jorgensen's patent application was filed. We regret the omission of this information from the original article.

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Apple Shuts Swift Mailing List, Migrates to Online Forum
 
An anonymous reader writes: Apple's Swift project "has completed the process of migrating to the Swift Forums as the primary method for discussion and communication!" announced a blog post on Friday. "The former mailing lists have been shut down and archived, and all mailing list content has been imported into the new forum system." While they're still maintaining a few Swift-related mailing lists, they're moving discussions into online forums divided into four main categories: Evolution, Development, Using Swift, and Site Feedback. Forum accounts can be set up using either email registration or GitHub accounts. It was one year ago that Swift creator Chris Lattner answered questions from Slashdot readers.

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InternetNews.com News Recent news from InternetNews.com

IT Earnings Way Up at Job Site Elance
 
Google App Engine, HTML5, search engine optimization and social media marketing are among the fastest movers on Elance's list of hot job opportunities available online.

Say What? The Week's Top Five IT Quotes
 
Google Wave crashes, fighting to keep mainframe skills alive, beware the Outernet and more.

GPL Enforcement Notches Another Victory
 
The license at the heart of many open source projects is amassing a winning record when it comes to successfully pursuing enforcement lawsuits.