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Re: Calculate/Interpolate size of y in x^y = z when you do know "number of digits z" and base x?

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From Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups comp.lang.javascript
Subject Re: Calculate/Interpolate size of y in x^y = z when you do know "number of digits z" and base x?
Date Mon, 11 May 2015 21:49:48 +0100
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jonas.thornvall@gmail.com writes:
<snip>
> An example using a small integer we search 2188 and base is 3. 
>
> So 2188=3^y   
> y is an integer.

I don't think that was obvious, but I suspect you don't need to know
this number.  You posted some code the uses this number but it was more
complicated than it needed to be.

> I think mathetmaticians use logarithms for this kind of problem, but i
> am not sure that is fastest approach. Maybe a search algorithm, or
> other approaches are faster when one know the number of digits?

If you use the number of digits, you *are* using logarithms.  That's
what a logarithm is.

<snip>
-- 
Ben.

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Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? jonas.thornvall@gmail.com - 2015-05-11 04:22 -0700
  Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? jonas.thornvall@gmail.com - 2015-05-11 04:28 -0700
    Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? jonas.thornvall@gmail.com - 2015-05-11 05:47 -0700
      Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-05-11 13:56 +0100
        Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? jonas.thornvall@gmail.com - 2015-05-11 06:12 -0700
          Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? jonas.thornvall@gmail.com - 2015-05-11 06:19 -0700
          Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-05-11 21:49 +0100
  Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-11 15:19 +0200
    Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? jonas.thornvall@gmail.com - 2015-05-11 06:25 -0700
    Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? jonas.thornvall@gmail.com - 2015-05-11 06:30 -0700
      Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-11 18:18 +0200
        Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? jonas.thornvall@gmail.com - 2015-05-11 09:32 -0700
          Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-11 19:45 +0200
            Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-05-11 22:58 +0200
              Re: Calculate/Interpolate size of y in  x^y = z  when you do know "number of  digits z" and  base  x? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-05-11 23:13 +0200

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