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From: Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups: comp.lang.javascript
Subject: Re: Best search algorithm to find a condition within a range.
Date: Tue, 07 Apr 2015 13:27:28 +0100
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jonas.thornvall@gmail.com writes:

> I want todo faster baseconversion for very big bases like base 1 000
> 000, so instead of adding up digits i search it.

The size of the base is immaterial, provided that it is in the range for
which arithmetic operations are exact.  1,000,000 is well within that
range.

<snip>
> <SCRIPT LANGUAGE="Javascript"> 
> //CONVERT A DECIMAL NUMBER INTO ANYBASE 
> function newbase(decNumber,base){ 

Your terms are wrong, and I don't think this is just a trivial detail --
I think maybe it points to something you've misunderstood.  The value in
"decNumber" is not decimal -- it's just a number.  Internally it is
represented in a very well-defined format that uses binary for both a
fraction and an exponent, but you don't need to care about that.  You
just want to do arithmetic on it.  (Maybe one day you will write a
routine like this that takes a bignum in base X and converts it to
bignum in base Y, but for the moment, you don't seem to be doing that at
all.)

Anyway, the algorithm for representing a number in base B is the same
whatever the base is: the least significant digit is obtained by using
the remainder operation (%) and you can move on to the next one by
dividing the number by the base.  I think you know this already.

<snip>
-- 
Ben.