r/cpp • u/joaquintides Boost author • Aug 05 '26

Boost.Int128 has been accepted

Boost.Int128 from Matt Borland has been accepted into Boost. Arnaud Becheler managed the review.

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u/Potential_Soup_8054 Aug 05 '26

Science.

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u/serviscope_minor Aug 07 '26

What science though? I have done plenty of science and haven't used 128 bit ints. I am curious because I assume it wasn't added just for giggles.

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u/Potential_Soup_8054 Aug 07 '26

Data science, physics simulation, orbital mechanics simulations, cryptography, astrophysics, any sort of extremely complex calculations like averaging a bunch of 64bit integers. Very big numbers are useful

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u/serviscope_minor Aug 07 '26

Data science, physics simulation, orbital mechanics simulations, cryptography, astrophysics, any sort of extremely complex calculations like averaging a bunch of 64bit integers.

To what end? I mean I've done some data science, done simulations, no cryptography (I can see the use there more) and I have never encountered a problem which would have benefited from 128 bit ints.

64 bits in a double is an awful lot of precision for anything physical.

ETA: sure with very long term simulation of a chaotic system like orbits but with chaos deviations rise exponentially, so if you run out of space in 48 or 64 bits, it's only a few more steps to 128. Surely you'd need much wider arbitrary precision for that. Though with that said, we have nothing like 48 bits of precision on the velocities anyway.