Toom-Cook 6-Way: Interpolation by Hand


Building a Toom-Cook 6-way multiplication, step by step. With comments but without the curses and the heavy math.
This is in large parts automatically translated from a Latex document to WordPress. Despite a lot of manual corrections I still have that vague idea that something is amiss or even wrong. At least the last listing works. Even Mozilla’s spellchecker failed!

1. Introduction

Why the hassle if Bodrati, Zanoni, Zimmerman or whoever comes to mind had already done it? It is simply a license problem. LibTomMath has a licence that is nearly indistinguishable from the construct Public Domain and hence cannot use any of the implementations. Bodrati for example puts all his works under the GPL.

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Tegenaria domestica

Tegenaria domestica (female))

Tegenaria domestica (female))

It’s officially winter now (yes, I’m late, as always) and the house spiders look for the warm and cozy and slightly humid places. The toilet might have been a good idea at first sight but it is not heated very well, just so much that the pipes don’t freeze. Yes, all pipes, thank you.

Sooo, this little girl (bit unsure, have not seen the underbelly but the lack of swollennes in the pedipalps hints in the direction of female) dropped herself into the little sink aside of the larger one and let me have a chance to do my good deed of the day and help her out of her misery. There you can see her waving good-bye before entering the underworld of the 70’s-green basin with all of that inviting nooks and crannies.

Arachnoday

Argiope bruennichi (wasp spider), dorsal

Argiope bruennichi (wasp spider), female (and male at the lower left?), dorsal

Once a very rare find at this place, so rare that I had to look it up to be sure but the typical zig-zag band and the lack of the quite distinct body-lobes of Argiope lobata gave it away. I don’t know if the wrapped spider at the lower left is indeed a male, I did not want to unwrap it. It also looks a bit too large for a male. The above picture has been slightly enhanced regarding colour saturation (not changes in hue!) and details, the two below the fold less so. (My camera is still a cheap digi-snapper without any ability to get the raw files).
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