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Re: Fourth root of integer

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Charles Richmond wrote:
> 
> On 5/16/11 8:46 AM, pete wrote:
> > Old Wolf wrote:
> >>
> >> Looking for an algorithm to find the fourth root of
> >> a large integer (I have a multi-precision integer
> >> library already). If there is no exact fourth root then
> >> the floor or ceiling is OK, I don't need a 'remainder'
> >> or anything.
> >>
> >> Any ideas?
> >
> > Why not just the square root of the square root?
> >
> 
> The fourth root of (2143/22) gives PI to about 8 decimal places.
> (Using your hand calculator, take the square root twice.)

The line in the original post which mentions
"no exact fourth root then the floor or ceiling is OK", 
suugests that OP is talking about integer math.

However, according to my calculator
                       (2143/22) == 97.409090909090909090909090909091
            square root(2143/22) == 9.8696043947612666756665932864345
square root(square root(2143/22))== 3.141592652582646125206037179644

So, I guess that I don't see your point.

-- 
pete

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Thread

Fourth root of integer Old Wolf <oldwolf@inspire.net.nz> - 2011-05-15 20:30 -0700
  Re: Fourth root of integer kym@kymhorsell.com - 2011-05-16 04:10 +0000
    Re: Fourth root of integer Jacob <asdf@hsu.edu> - 2011-05-16 02:49 -0400
  Re: Fourth root of integer pete <pfiland@mindspring.com> - 2011-05-16 09:46 -0400
    Re: Fourth root of integer Charles Richmond <frizzle@tx.rr.com> - 2011-05-16 22:39 -0500
      Re: Fourth root of integer pete <pfiland@mindspring.com> - 2011-05-17 09:17 -0400
  Re: Fourth root of integer rossum <rossum48@coldmail.com> - 2011-05-16 16:41 +0100
  Re: Fourth root of integer Ralph Boland <rpboland@gmail.com> - 2011-05-16 11:06 -0700
  Re: Fourth root of integer Dann Corbit <dcorbit@connx.com> - 2011-05-16 13:28 -0700
    Re: Fourth root of integer Christopher Henrich <chenrich@monmouth.com> - 2011-05-18 23:41 -0400
      Re: Fourth root of integer rossum <rossum48@coldmail.com> - 2011-05-19 09:54 +0100
        Re: Fourth root of integer Christopher Henrich <chenrich@monmouth.com> - 2011-05-20 15:16 -0400
      Re: Fourth root of integer - fourth-root.mws [1/1] Dann Corbit <dcorbit@connx.com> - 2011-05-20 12:42 -0700
        Re: Fourth root of integer - fourth-root.mws [1/1] Christopher Henrich <chenrich@monmouth.com> - 2011-05-20 16:10 -0400
    Re: Fourth root of integer James Waldby <not@valid.invalid> - 2011-05-19 07:01 +0000
      Re: Fourth root of integer James Waldby <not@valid.invalid> - 2011-05-21 00:37 +0000

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