Viewing profile — simonbyrne

If that's seriously what you're looking for, you should really consider Fortran. There is a reason it is still very widely used in scientific domains.

You can just wrap the literal in a conversion function, eg Float32(0x1p52), which should get constant propagated at compile time.

That's fascinating thread, thanks: https://github.com/WebAssembly/design/issues/148

Do you know what happens when you have ops with different flags? e.g. if you have (a + b) + c, where one + allows reassoc but one doesn't?

From personal experience, yes: I've seen multiple cases of scientists finding the ultimate cause of their bugs was some fast-math-related optimization. The problem isn't necessaril…

I tried to lay out a reasonable path: incrementally test accuracy and performance, and only enable the necessary optimizations to get the desired performance. Good tests will catch…

I'm not exactly sure what you're asking here, but the point is that "to machine precision" is relative: if f(x) and g(x) are O(1e200), then the absolute error of each is still O(1e…

The key thing about floating point is that it maintains relative accuracy: in your case, if you have say f(x) and g(x) are both O(1e200), and are correct to some small relative tol…

Herbie is a great tool, especially for teaching.

In theory, every function should do that to check things like rounding mode etc. But that would be pretty slow, especially for low-latency operations (modifying mxcsr will disrupt …

-ffp-contract=fast will enable FMA contraction, i.e. replacing a * b + c with fma(a,b,c). This is generally okay, but there are a few cases where it can cause problems: the canonic…

My point isn't that fast-math isn't useful: it very much is. The problem is that it is a whole grab bag of things that can do very dangerous things. Rather than using a sledgehamme…

Not necessarily: if your cospi(x) function is always returning 1.0 ( https://github.com/JuliaLang/julia/issues/30073#issuecomment... ), but you wrote your code assuming the result …

> But then people latched on to the idea that it was caused by some kind of sonic device or hitherto unknown weapon targeting embassies. Possibly prompted by historical precedent: …

One of the interesting things about the 80-bit format was that allowed the use of 64-bit integers on a 16 or 32-bit machine. This was what Thomas Nicely was using them for when he …

> or wait for optimizations to be done, e.g have pandas, numpy etc handle multi-core processors etc ? All those exist already. Indeed, other than DataFrames.jl (the pandas equivale…

I disagree about practical and accessible: - its exposition is complicated (trying to prove everything in a general base makes it difficult to understand) - it's woefully out of da…

Deep learning is the obvious answer: 10 years ago it was largely confined to a small number of research groups and niche conferences.

Thank you! The Goldberg article is a terrible way to learn about floating point, and the frequency with which it is referred to on StackOverflow is really disheartening.

I seem to recall that part of the DoE's selection criteria is to ensure a competitive market for future contracts (since they will always be buying more supercomputers). Given the …

Additionally the language and penalties for fare evasion often don't match that of say parking tickets, which I would put as roughly similar in terms of moral violations (i.e. taki…

Not to mention a Cray 1 used 115kW: the new raspberry pi uses 7W peak.

It's difficult to examine his comments without historical context: I haven't dealt with any code from that era, but there is still plenty of Fortran 77 code from ~20 years later wh…

Am I missing something? Other than the doc generator (which is in Python), none of the repos have been touched for a year or so.