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NoiseLang: Where N = 5 is a Dirac delta

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Re: NoiseLang: Where N = 5 is a Dirac delta

#51

Post by manucorporat »

thrtythreeforty wrote: post #33
manucorporat wrote: post #27

Earlier quoted context omitted.

I was exploring ways to speed up this language, the naive implementation is just a interpreter executed in rust, which can just do so much. Once thing i explored was to compile the program graph into WASM, then execute WASM. The idea is the the WASM runtime would JIT program and run faster than any interpreter I could write myself. During this exploration, i found that I could use the JIT optimizer directly and skip…

Surely SIMD combined with multiple streams would beat both approaches. (This would be separate streams in each SIMD lane and separate streams in different SIMD variables.) There are multiple SIMD execution units, just like the 6 scalar units you mention. The latency of SIMD ops will be similar to scalar, except in cases you mention like shifts.

gonna try it! i also suspect that that cranelift's vector lowering is not ideal, so the reasons i described could be wrong

Re: NoiseLang: Where N = 5 is a Dirac delta

#52

Post by TheOtherHobbes »

ajkjk wrote: post #44
seanhunter wrote: post #21

Does it still count as a Dirac delta when it’s a discrete distribution? (The distributions in TFA are not continuous - they are things like a roll of 1d6 etc)

Some people would call it a Kronecker delta instead, but imo they are exactly the same concept. The Kronecker delta is the indicator for a single value, like 1_{x=0}, while the Dirac delta is the indicator for a single 'dx' partition, divided by the width of the partition: δ(x) = 1_{0 in (x, x+dx)}/|dx| which is why integrating it ∫ δ(x) dx = ∫ 1_{0 in (x, x+dx)}/|dx| = ±1 (depending on the orientation of the integra…

Dirac delta is infinitely tall. Kronecker delta has a height of 1. Both are infinitely thin. Much used in DSP.

Re: NoiseLang: Where N = 5 is a Dirac delta

#53

Post by mswphd »

chromoblob wrote: post #45
mswphd wrote: post #23

Earlier quoted context omitted.

note that similar concepts appear in mathematics. Generally the term for it is a "mollified" function. applied to the step function, you would get a smooth cutoff function https://en.wikipedia.org/wiki/Mollifier#Smooth_cutoff_functi... this is also related somewhat to the notion of differentiable programming. RELU is (roughly) the same as x * step(x). In differentiable programming one can replace it with smooth appro…

Secret data flow should be directly controlled by programming language features. It's ugly that people are resorting to wrestling the compiler using such distant means as purity, applied in roundabout way.

there's been some forward movement on doing this via an appropriate intrinsic in LLVM

https://github.com/llvm/llvm-project/pull/166702

note that this isn't the only "trick" needed for constant-time programming though. Indexing an array with a secret index needs its own trick, for example.

I agree that trying to trick the compiler is very ugly. A well-known applied cryptographer has a paper from last year saying that not only is it ugly, but it doesn't work particularly well, and if anything the trendline of the various "tricks" is that they get less effective over time.

https://eprint.iacr.org/2025/435

Re: NoiseLang: Where N = 5 is a Dirac delta

#55

Post by ajkjk »

TheOtherHobbes wrote: post #52
ajkjk wrote: post #44

Earlier quoted context omitted.

Some people would call it a Kronecker delta instead, but imo they are exactly the same concept. The Kronecker delta is the indicator for a single value, like 1_{x=0}, while the Dirac delta is the indicator for a single 'dx' partition, divided by the width of the partition: δ(x) = 1_{0 in (x, x+dx)}/|dx| which is why integrating it ∫ δ(x) dx = ∫ 1_{0 in (x, x+dx)}/|dx| = ±1 (depending on the orientation of the integra…

Dirac delta is infinitely tall. Kronecker delta has a height of 1. Both are infinitely thin. Much used in DSP.

I think you have missed my point. Both are defined to integrate to one, over different measures.

Re: NoiseLang: Where N = 5 is a Dirac delta

#57

Post by tengwar2 »

manucorporat wrote: post #16
tengwar2 wrote: post #12

Earlier quoted context omitted.

Firstly, I'm not intending any slight on you personally! In fact this might be more of an issue for you interacting with the site than for people just reading an article. There are multiple versions of the list. The authoritative site appears to be https://github.com/hagezi/dns-blocklists , and making a fairly random choice, I used the "medium" version of the "Threat intelligence feed", and specifically the one marke…

This is great! thank you for the digging, gonna figuring out how it end up there

Just checked, and it's gone from the list. Did you happen to find out what the problem was?
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