Fredrik Johansson

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Fredrik Johansson

Fredrik Johansson

@hypergeometer

fredrikj @ mathstodon Computer algebra & Arbitrary-precision arithmetic. Researcher at @Inria.

Bordeaux, France Se unió Mart 2016
128 Siguiendo620 Seguidores
Fredrik Johansson
Fredrik Johansson@hypergeometer·
@oscarsm85309043 If you want to do this many times with a fixed modulus, then yes: you can precompute an inverse of n, or use Montgomery reduction. You can also do things more efficiently for n of special form, e.g. n = 2^k+1.
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oscar smith
oscar smith@oscarsm85309043·
@hypergeometer Nice improvement! Relatedly, I've wondered for a while if there is a more efficient way to compute a*b%n than doing the multiplication and then the modulo. Any thoughts?
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Fredrik Johansson
Fredrik Johansson@hypergeometer·
fredrikj.net/blog/2023/04/f… FLINT furnished with faster FFT: we recently merged Dan Schultz's amazing new small-prime FFT code into FLINT, enabling much faster bignum arithmetic (in some cases 10x faster than GMP).
Fredrik Johansson tweet media
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Fredrik Johansson
Fredrik Johansson@hypergeometer·
@hcohl001 Here, or in a different medium? FLINT (flintlib.org) is a C library for computational number theory and basic computer algebra functionality. It does exact or arbitrary-precision integers, rationals, number fields, reals, polynomials, matrices, etc.
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Fredrik Johansson
Fredrik Johansson@hypergeometer·
In case you missed it: FLINT, Antic, Arb, Calcium and Generic-Rings have merged into a single project: what will be FLINT 3.x going forward. The 3.0 release will happen later this year; I'm currently working on debloating this 1 MLOC codebase. github.com/flintlib/flint2
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Fredrik Johansson
Fredrik Johansson@hypergeometer·
I have removed the links to Twitter on my website. See you all on that other social network instead!
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Fredrik Johansson retuiteado
Deyan Ginev
Deyan Ginev@dginev·
LaTeXML 0.8.7 was just released! We're ready for #MathML Core. With gratitude to the wider community, who helped drive another productive year of extending our TeX interpretation fidelity and our LaTeX ecosystem coverage. Full release notes at: github.com/brucemiller/La…
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Fredrik Johansson
Fredrik Johansson@hypergeometer·
There's currently a 7 month delay just to get the *appointment* for a national ID card or passport here. So much for free movement within Schengen 😡
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Fredrik Johansson
Fredrik Johansson@hypergeometer·
Anyone interested in a full-time job doing FLINT development should get in touch. I don't have funding at the moment, but given a qualified candidate (skilled with computer algebra *and* C programming), there's a decent chance that funding can be found.
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Fredrik Johansson
Fredrik Johansson@hypergeometer·
@avihu28 Helping maintain wrappers like Python-FLINT could be part of the job. With that said, it's a public project and anyone is free to contribute right now! Personally, I'm planning a rewrite of Python-FLINT when/if I get the generics module for FLINT fully working.
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Fredrik Johansson
Fredrik Johansson@hypergeometer·
Sadly proof assistants are still quite limited when it comes to (complex) analysis, and computer algebra systems suck at handling inequalities. I wish we had proper "computer analysis systems" making computer-verified classical analysis truly routine.
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Fredrik Johansson
Fredrik Johansson@hypergeometer·
Many proofs in analytic number theory look like this, and I can never quite shake the fear that the author might have dropped a decimal or a sign or a residue somewhere.
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Fredrik Johansson
Fredrik Johansson@hypergeometer·
What strikes me about Yitang Zhang's preprint is that there doesn't seem to be any fancy math (I could be wrong about this), just 100+ pages of tedious analytic calculations. An interesting candidate for computer verification?
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Ivo Dujmovic
Ivo Dujmovic@ivo2d·
@hypergeometer Can you please grant someone git privs to create a new release of mpmath? :)
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Fredrik Johansson retuiteado
William Stein
William Stein@wstein389·
I finally launched CoWasm.org. It's kind of like @emscripten, but built using @ziglang, with first class support for both servers and browsers. The main package is @python 3.11, but there are lots of other fun #webassembly ports hidden inside...
William Stein tweet media
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Fredrik Johansson retuiteado
Michael Eisen
Michael Eisen@mbeisen·
Accepting and rejecting papers is an archaic practice that is terrible for science. It strips peer review of its value & institutionalizes the practice of judging scientists based on where, rather than what, they publish. It's time for this system to go. elifesciences.org/articles/83889
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