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From: Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups: comp.lang.javascript
Subject: Re: Improve speed calculations?
Date: Mon, 11 Jan 2016 13:28:10 +0000
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jonas.thornvall@gmail.com writes:

> Den söndag 10 januari 2016 kl. 14:33:27 UTC+1 skrev jonas.t...@gmail.com:
>> <script language="Javascript">
<snip code>
> http://jt.node365.se/BAUTABASE.html
>
> Using the biggest base possible adding "4503599627370495" encoding
> fibonacci in javascript without overflow.
>
> Also fixed ambiguity reading out the numbers in bases over ten by
> using separator for digitplaces. The add can not cause overflow but to
> get rid of base overflow would require some real deep thinking.
>
> The 100000th Fibonacci took 34 seconds i do not think i can get it
> much faster in javascript if your a wizard please prove me wrong.

I have not tried your code, but I've just written a quick bignum add
function and I can get fib(100000) in about 3.5 seconds.  If I have time
to unravel yours, I'll do a comparative test.  Note that a language with
a good bignum type (Haskell, for example) will do it in less than 100th
of a second.

Note that your 'challenge' makes it easy to optimise the code.  For
example, using a power of 10 as the base makes the conversion for
printing very simple.

-- 
Ben.