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Groups > comp.lang.javascript > #27336
| Newsgroups | comp.lang.javascript |
|---|---|
| Date | 2015-04-12 07:20 -0700 |
| References | <57012849-2075-447d-8945-b52c8918a502@googlegroups.com> |
| Message-ID | <104f068d-5f5f-4580-aa3a-e25f2a68c064@googlegroups.com> (permalink) |
| Subject | Re: Convoluted logic trying to do bignumb |
| From | jonas.thornvall@gmail.com |
Den fredag 10 april 2015 kl. 07:26:56 UTC+2 skrev jonas.t...@gmail.com:
> I try to change the basechanger to work with bignumb, but my logic find it hard.
> I move decnumber, base and the exponent(digArr) into arrays.
>
> And the function doing multiplication does take the base and two arrays as arguments..
> But i feel clueless about howto do the comparission, within the loop?
> Of course i can check before loop, but it seem i have to make the check mutliplication within the loop using an IF clause? And if the condition true i really do it?
>
> But the actual IF clause now comparing the values of two multiplicated arrays vs the value of a third array.
>
>
> [EXAMPLE] Code should compare a number to the ***nearest smaller exponent*** in base of choice e.g find x in 10^x that or in binary 2^x without causing overflow.
>
>
> var digArr=[];
>
> digArr[1]=1;
>
> numbArr=decNumber.split("");
>
> baseArr=base.split("");
>
> while(digArr*baseArr<=numbArr){
>
> digmult=naiveMult(base,base,digmult);
>
> digits++;
> }
Well the overflowcheck realitycheck is to come when i actually implemented bignumb arithmecit in anybase.
It will turn back the factors in the chosen base and the products into decimal base. And divide the product to check.
I had a good morning changing the approach, i do not touch the bignumb function because they work, i do minimal changes to the baseconverter just enough to make it bignumb.
5 more lines of code and i am there, i realised there is no need for division since the multiples of exponent already calculated.
Bot at some point of course a bignumb division should be implemented, and if i recall correct it is basicly multiplication.
When that is done i will replace adding up digits in the exponent digitplaces, with a searchalgorithm Stein's GCD. I have a slight memory how one can make it faster than binary search.
One can also look at the length(digits) to decide if an addup or a search is optimal, i think the ***biggest base*** that can be used without to make base an array is SQRT 4294967295 = 65535 without ever causing overflow. But that is pretty good to be able to bignumb modular arithmetic in base 65535, although i would prefer arbitrary sized without overflow, it just to much changes needed right now.
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Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-09 22:26 -0700
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-09 22:44 -0700
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-09 22:59 -0700
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-09 23:02 -0700
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-09 23:16 -0700
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-10 01:49 -0700
Re: Convoluted logic trying to do bignumb "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-04-10 11:53 +0200
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-10 06:33 -0700
Re: Convoluted logic trying to do bignumb "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-04-10 20:25 +0200
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-10 11:55 -0700
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-11 04:05 -0700
Re: Convoluted logic trying to do bignumb "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-04-11 13:13 +0200
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-11 04:49 -0700
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-11 04:56 -0700
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-11 05:31 -0700
Re: Convoluted logic trying to do bignumb "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-04-11 20:22 +0200
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-11 12:07 -0700
Re: Convoluted logic trying to do bignumb "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-04-11 21:32 +0200
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-11 13:22 -0700
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-11 16:07 -0700
Re: Convoluted logic trying to do bignumb "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-04-12 12:06 +0200
Re: Convoluted logic trying to do bignumb Dr J R Stockton <reply1500@merlyn.demon.co.uk.invalid> - 2015-04-14 22:44 +0100
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-15 02:39 -0700
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-15 04:52 -0700
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-15 05:09 -0700
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-15 05:10 -0700
Re: Convoluted logic trying to do bignumb Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-04-15 22:46 +0100
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-16 01:06 -0700
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-11 07:21 -0700
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-11 08:06 -0700
Re: Convoluted logic trying to do bignumb "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-04-11 20:32 +0200
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-11 12:10 -0700
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-10 06:55 -0700
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-10 07:19 -0700
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-10 07:26 -0700
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-12 07:20 -0700
Re: Convoluted logic trying to do bignumb "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-04-12 17:30 +0200
Re: Convoluted logic trying to do bignumb jonas.thornvall@gmail.com - 2015-04-12 09:03 -0700
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