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by defrost 1103 days ago
> Addition modulo N is used only in niche cases like cryptography.

... and niche cases like GIS location computations on a spherical planet and any form of engineering | physics mesh computation.

It's inescapable when you peer into the guts of any earth based modelling from satellte data .. something that happens on a daily terrabyte scale.
2 comments
ghusbands 1103 days ago
Even if there are some more cases, the basic point is still true: The majority of additions don't warrant word-size wrapping and it has been a source of many, many bugs.
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rcxdude 1102 days ago
Which is almost never wrapping at a power of two, unless you scale your coordinate system to optimise it.
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defrost 1102 days ago
The quote I responded to was:

> Addition modulo N is used only in niche cases ...

and not modulo 2^N.

The point that I would make is that general purpose CPU's doing general everday tasks such as https connections, secure transfers, GIS mapping, etc are doing a great many more modulo operations than acknowledged above.

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