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From: Richard Kettlewell <invalid@invalid.invalid>
Newsgroups: comp.os.linux.advocacy,comp.os.linux.misc
Subject: Re: Rewriting SSA. Is This A Chance For GNU/Linux?
Date: Sun, 06 Apr 2025 10:05:34 +0100
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The Natural Philosopher <tnp@invalid.invalid> writes:
> On 05/04/2025 22:57, Richard Kettlewell wrote:
>> The Natural Philosopher <tnp@invalid.invalid> writes:
>>>   Analogue multiplication is the holy grail and can be dome using the
>>>   exponential characteristics of bipolar transistors
>>>
>>> https://www.analog.com/media/en/technical-documentation/data-sheets/ADL5391.pdf
>> The electronics there is far beyond me but how general (and how
>> reliable) can this be made?
>> 
> Well it isn't very general. It takes two voltages between on and one
> an multiplies them together.
> That's what it does.
>
> Going from digits to volts is relatively fast and easy, but the
> reverse is not so true

Right, probably not a fit for my application, then.

>> The operations I’m currently interested in are modular multiplication,
>> addition and subtraction with comparatively small moduli (12-bit and
>> 23-bit, currently). It’s a well-undertood problem with digital
>> computation, of course, but I’m curious about whether there’s another
>> option here.
> 
> That flew over my head Richard. Advanced maths is not my forte ...

You do modular arithmetic whenever you do times and dates - informally,
it’s the same thing as they way minutes and seconds wrap around from 59
to 0, hours from 23 to 0, etc.

Putting it together into something useful is a bit more than that,
though, indeed, and a persistent concern is how to do it faster, hence
keeping an eye out for additional technology options.

-- 
https://www.greenend.org.uk/rjk/