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From: Paul Rubin <no.email@nospam.invalid>
Newsgroups: comp.lang.forth
Subject: Re: Parsing timestamps?
Date: Mon, 14 Jul 2025 11:31:24 -0700
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mhx@iae.nl (mhx) writes:
> This looks very interesting. I can find Kahan and Neumaier, but
> "tree addition" didn't turn up (There is a suspicious looking
> reliability paper about the approach which surely is not what
> you meant). Or is it pairwise addition what I should look for?

I think the idea is to treat (say) a 1024 element sum into two
512-element sums that you compute separately, then add the results
together.  You do the 512-element sums the same way, recursively.
Sometimes you can parallelize the computations, and depending on the CPU
you might be able to use vector or SIMD instructions once the chunks are
small enough.