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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 14:23:42 +0100
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jonas.thornvall@gmail.com writes:

> Den tisdag 7 april 2015 kl. 14:27:36 UTC+2 skrev Ben Bacarisse:
>> 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. 
>
> No you are wrong, the input is an integer and that is a number encoded
> in base 10, there is no such thing as just a number.

The input has happened.  The number is now represent internally as
javascript represents numbers.  It's not decimal and it's best to ignore
how it is represented.

You are right that, in a computer, there are no things that are "just
numbers" (they always have some sort of representation), but rather
misses the point of my post -- the algorithm to represent a number in
some base does not depend on how the number is represented.  You can
simplify some cases, of course -- if you know a number is internally in
binary converting to base 16 can be made very simple, but these are
exceptions, not the general rule.

<snip>
> I aim to replace the slow add when dealing with real big bases with a
> search.  

I thought your post was about converting between bases.  If it wasn't,
just ignore my comments.

-- 
Ben.