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> One cannot expect a compiler to come up with such encoding.

One could, however, imagine a sufficiently expressive language that allows the developer to specify the encoding schema without resorting to raw 64-bit words.


This breaks the language. Do you want safety or do you want expression?

+1. I've used this with Lattice UP5K for some experimental development. I wanted to be able to quickly skip between working on Windows and Linux. Worked well at the time.

Seems legit. My only question is whether a developer has sufficient copyright to grant such a license.

> disk heads to optimized queued reads of data in a “traveling salesman” sort of way

Luckily the read heads only have one degree of freedom, so the "elevator algorithm" is sufficient: https://en.wikipedia.org/wiki/Elevator_algorithm


The essential concepts of mathematical reasoning, if there are such things, are the concern of mathematical logicians, or maybe even psychologists, not, in general, of working mathematicians. One of my professors once told me something to the effect of "if you think you are going to learn any of that here, you are in the wrong place."

If you are interested in Terence Tao's personal mathematical inner world, he touches on that during his interview with Lex Friedman, which I think you might find interesting. Interviews with Kevin Buzzard sometimes touch on these themes too.


"maybe even psychologists" -- unironically true, but maybe I am talking about something different from you. The basis of (higher-level) math seem to mostly be "am I psychologically (emotionally...?) comfortable with accepting annoying ideas?" At least from my experience.

Thank you, I will watch these interviews!

If you want to follow Terence Tao's new interviews, podcasts, blog posts, etc. and get an email delivered promptly to your inbox, you can do it here: https://recordal.app/people/terence-tao

Disclaimer: I built this tool a couple of weeks back.


CBT is not a first line treatment for ADHD in Australia. Indeed standard CBT is contra-indicated because it requires the kind of "homework" that ADHDers struggle with. There are CBT variants tailored for ADHD however.

Russel Barkley is a pioneer in the field of ADHD research. I have heard of such a claim, but not from Russel Barkley. Could you provide a link of Russel Barkley making the claim please?

It's somewhere in this talk (broken down as a playlist). It's been a while since I've watched it but I do recall him saying that they can see physically differences in the brain of adhd folks

https://www.youtube.com/watch?v=BzhbAK1pdPM&list=PLzBixSjmbc...


Seeing physical differences in brain volume, connectivity or activity between groups of many adhd folks and non-adhd folks is one thing and that can be done. However, performing a clinical diagnosis of adhd in an individual, solely based on a brain scan, is a completely different thing.

> It's competing with a $200/mo subscription or renting server gpu time

Not if you're an enterprise that wants or requires on-prem inference.


if you're one of those enterprises it's perfectly reasonable to assume you're more likely to go have your procurement and legal teams negotiate with google for one of those weird boxes to run gemini on prem (https://cloud.google.com/blog/products/ai-machine-learning/r...) or other enterprise-y nonsense vs buying consumer hardware to run a chinese large language model in your network. I do not envy the person at a company having to get approval model by model because of weird open source licensing terms dealing with the "how do we know chinese models are safe" question (hopefully they're at least getting asked in the context of hooking it into an agent harness so there's some sort of plausible risk that necessitates the conversation - i can very much imagine it getting shut down to even run in a sandbox because chinese model + people being scared after the huggingface stuff). There's a lot of reasons to assume enterprise wouldn't be interested, and it's very very cool that they are IMO. Anthropic cut claude code rate limits - they dont seem to be see open source llms as a market threat (rhtetoric to the white house aside) yet but enterprises being willing to run consumer hardware to run local models could make things a bit more tangible

Wouldn't enterprises investing in their own hardware be more likely to buy standard 4-GPU or 8-GPU servers? Apple machines aren't really designed for server racks.

Daniel Lemire specialises in high-performance algorithm implementation. In recent years he has been impressed by specific performance characteristics of Apple's CPUs. For example, their ability to eek out the maximum possible throughput from a given instruction stream's data dependencies. My information may be stale, but when I read Daniel's comments I assume that Apple is being used for compariosn because it is the current leader, and take it as given that AMD and Intel are behind. You can probably find sources where he makes head-to-head comparisons with AMD and Intel. If you're not familiar with his work I can recommend it. The Wookash podcast interview is a gentle introduction, there is open source code and academic papers if that's more your thing.


x and y are integers represented as floating point

  > d = trunc(x/y);     // floor works for unsigned
  >
  > // NOTE: if only want 'd' and it's being converted to an
  > // integer then the truncate or floor operation is
  > // free in the float to integer conversion.
Please show me how to portably truncate or floor a floating point value to an int in C for "free".


They're typically like a 3-cycle op, right? Obviously that's not zero, but as far as floating point ops get it's a cheap as it gets, like an add, mul, fma, that sorta thing.


I am probably dating myself here, but in C the default rounding mode is round-to-nearest and the cost of switching the x86 FPU to truncate (and back) in order to perform the truncation is extremely expensive. Perhaps other instruction sets have truncate-to-integer instructions that ignore the active rounding mode.


I think you misread?

{within float-to-integer conversion} trunc or floor is free

that is, if you are converting, you already get it by default


I think you are correct. Clearly I am still traumatised by the cost of converting floats to ints in the x86 era.


Perhaps they meant implicit instead of free, since the comment also explains that `d` is an integer and the intent is to truncate, so the trunc() call is not even necessary when the assigning type is an int.


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