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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.