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From: Krishna Myneni <krishna.myneni@ccreweb.org>
Newsgroups: comp.lang.forth
Subject: Re: exercise in double number arithmetic
Date: Sat, 6 Jul 2024 18:50:28 -0500
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On 7/6/24 16:59, Ahmed wrote:
> Why using double arithmetic when we can use simply Pascal triangle?
> ...

Yes! I had forgotten about Pascal's triangle when I coded my solution. A 
benefit of your double number solution is that it works on both 32-bit 
and 64-bit Forth systems.

Here's my solution for the specific problem, which will only work on a 
64-bit system:

: solution ( -- d)
     1 s>d 43 22 do i 1 m*/ loop d>f
     21 dup s>d rot 2 do I 1 m*/ loop d>f
     f/ fround f>d ;

We don't have D/ in the standard, which necessitated the conversion to 
float for dividing two double length numbers and then convert back to 
double.

--
Krishna