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HP Patents Bignum Implementation From 1912

Posted by kdawson on from the can-you-spell-prior-art dept.

I Don't Believe in Imaginary Property writes "The authors of GMP (the GNU Multiple Precision Arithmetic Library) were invited to join Peer-to-Patent to review HP's recent patent on a very old technique for implementing bignums because their software might infringe. Basically, HP's patent claims choosing an exponent based on processor word size. If you choose a 4-bit word size and a binary number, you end up working in hexadecimal. Or for a computer with a 16-bit word and a base-10 number, you use base 10,000 so that each digit of the base-10,000 number would fit into a single 16-bit word. The obvious problem with that is that there's plenty of prior art here. Someone who spent a few minutes Googling found that Knuth describing the idea in TAOCP Vol. 2 and other citations go back to 1912 (which implemented the same algorithm using strips of cardboard and a calculating machine). None of this can be found in the 'references cited' section. Even though the patent examiner did add a couple of references, they appear to have cited some old patents. The patent issued a few months ago was filed back in October of 2004, and collected dust at the USPTO for some 834 days."

3 of 144 comments (clear)

  1. Now if we only knew what the patent was about! by radtea · · Score: 0, Troll

    I wish the summary said something about what the patent was about. I guess I'll check back in a few hours and scroll down to read the explanation that someone who has actually bothered to read and understand the claims has posted--I can't be bothered to be that guy this time, but I'm sure someone else will do it.

    Just think, if /. summaries on these stories bothered to tell us what the patent was about we could all be spared that effort, but we all know from long experience that they don't, so there's no point in responding to the summary with outrage unless you want to look like a completely newless clewbie.

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    Blasphemy is a human right. Blasphemophobia kills.
  2. 10,000??? by istartedi · · Score: 0, Troll

    10,000??? Turn in your geek card now. Don't understand why it should be turned in? Well, there are 10 types of people...

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    For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
  3. OK, nevermind by istartedi · · Score: 0, Troll

    I read it too fast, saw a number that wasn't a power of 2, and got snarky. Not sure about my geek card; but at least I'm in line with Slashdot community values.

    --
    For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?