Messages in this thread |  | | | From | Roland Kuhn <> | | Subject | Re: [RFC] div64_64 support | | Date | Tue, 6 Mar 2007 16:10:08 +0100 |
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Hi Andi!
On 6 Mar 2007, at 15:45, Andi Kleen wrote:
>> <rant> >> Let me see... You throw code like that and expect someone to actually >> understand it in one year, and be able to correct a bug ? > > To be honest I don't expect any bugs in this function. > >> </rant> >> >> Please add something, an URL or even better a nice explanation, >> per favor... > > It's straight out of Hacker's delight which is referenced in the > commit > log. > And it's pretty neat, too. Hint: (y+1)**3 = y**3 + 3*y**2 + 3*y + 1. The algorithm is exactly the same as for calculating the cubic root on paper, digit by digit. I found that algo in the school notebook of my grandpa (late 1920ies), a pity that it's not taught anymore... pocket calculators _do_ have downsides ;-)
Ciao, Roland
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