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From: Gerry Jackson <do-not-use@swldwa.uk>
Newsgroups: comp.lang.forth
Subject: Re: exercise in double number arithmetic
Date: Wed, 10 Jul 2024 08:51:02 +0100
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On 08/07/2024 13:30, Krishna Myneni wrote:
> On 7/7/24 09:33, Gerry Jackson wrote:
>> On 07/07/2024 14:17, Krishna Myneni wrote:
> ...
>>> The whole D>F and floating point operations can be dispensed with if 
>>> we have D/MOD -- a double length version /MOD.
>>>
>>> -- 
>>> Krishna
>>>
>>>
>>
>> There is a +D/MOD in this link
>>
>> http://www3.cs.stonybrook.edu/~algorith/implement/random-number/distrib/r250.seq
>>
> 
> Thanks, Gerry. It looks like D/MOD is not essential to computing the 
> binomial coefficients with double length numbers. We can use M*/ for 
> single computations, or simply D+ to build up a table of coefficients. 
> But, it's good to have a reference for D/MOD.
> 
> I remember that I wanted to update the FSL R250 code to generate 64-bit 
> random numbers, but I never got around to it. There is also a 
> permutations and combinations module in FSL which may benefit from what 
> has been demonstrated in this thread.
> 
> -- 
> Krishna
> 

I didn't realise the paper I linked to was in the FSL as I've never had 
much to do with the FSL. I found I had another definition for D/MOD from 
Forth Dimensions Vol 14 Issue 6, p 27 "Math - Who Needs It"
https://www.forth.org/fd/FD-V14N6.pdf
I've no idea how good it is


-- 
Gerry