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johnbcoughlin

230 karma · joined May 8, 2020

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johnbcoughlin··on Doing nothing at work
That does sound nice. I think the author would say that if it's part of your annual performance review, then you are being paid to do it. That's the real test, not the job description, which can't be expected to describe every single thing you end up doing once employed.
johnbcoughlin··on Doing nothing at work
I read the section you quoted as being about saving the day in an incident that's already in progress.
johnbcoughlin··on Doing nothing at work
The quoted section is about stepping in early with the right knowledge to fix an incident that's in progress. That is, putting out the fire.
johnbcoughlin··on You can't design software you don't work on
if you have some purported improvement to a codebase that would make it inconsistent, then it's a matter of taste, not fact, whether it is actually an improvement.
johnbcoughlin··on Seeing like a software company
You seem to have misunderstood the point being made in the section you quoted. The items are not on the list because it is a list of benefits that accrue to the company from work being legible. "Making money" is not a direct outcome of legibility, although it is a second or third-order effect.
johnbcoughlin··on Seeing like a software company
> Imagine if you brain had to be consciously aware of every breath you take, every time you move a finger, etc... you'd get nothing done. Same deal if a CEO has to be aware of and approve accelerating your unit tests with parallelism or whatever.

This is a strawman. No competent CEO thinks they need to be on top of your unit testing practices. The levels of legibility that companies actually aim for are much more defensible.

johnbcoughlin··on Beating the L1 cache with value speculation (2021)
Such optimizations may be forbidden by the fact that floating point addition is not associative unless you tell the compiler not to worry about that (I believe)
johnbcoughlin··on I've stopped using box plots (2021)
I can't see why a jitter plot with dark lines marking the quartile wouldn't be strictly better for this.
johnbcoughlin··on HH70, the first high-temperature superconducting Tokamak achieves first plasma
I doubt they have achieved any fusion reactions. They don't state any numbers on density or temperature so it's impossible to know. But in general plasma is never "caused by" fusion. Creating a plasma is quite easy compared to getting it hot and dense enough to fuse.
johnbcoughlin··on HH70, the first high-temperature superconducting Tokamak achieves first plasma
You don't ever create plasma via fusion, fusion occurs in plasma that has reached a certain temperature and density threshold.
johnbcoughlin··on If gravity isn't a force, then why does it "need" a boson?
I think the burden of explanation is on the great great grandparent post which proposed an accelerometer "entirely made out of the same magnetic field" which would let it satisfy an equivalence principle for "magnetic force".
johnbcoughlin··on Tests show high-temperature superconducting magnets are ready for fusion
It means nothing for ITER unfortunately. Changing the toroidal field strength implies a totally different plasma size, density, temperature, everything. ITER isn't designed for this strong of fields and the plasma they would confine.
johnbcoughlin··on Our Generation Ships Will Sink (2015)
The author of the article is Kim Stanley Robinson, whose Mars Trilogy and novel 2312 include all of the possible in-solar system alternatives you mention and more.
johnbcoughlin··on Strong arrows: a new approach to gradual typing
What does "most applications" mean?
johnbcoughlin··on VkFFT: Vulkan/CUDA/Hip/OpenCL/Level Zero/Metal Fast Fourier Transform Library
The FFT is rarely the only thing you're doing, so at the very least you get to keep the data local if it was already on gpu.
johnbcoughlin··on Amprius High-Density Batteries
It didn't, it did the subtraction in lbs and got the right answer, the off-by-one is due to rounding.
johnbcoughlin··on John Carmack’s ‘Different Path’ to Artificial General Intelligence
As long as you say it, you're okay with slavery when it's for the right person.
johnbcoughlin··on NYSE Tuesday opening mayhem traced to a staffer who left a backup system running
Matt Levine suggested that the chaos after opening was mainly due to market orders executing at ridiculous prices. Like, a limit buy for half the "real price" is the first buy order to get in the door, and that gets matched with a market sell order.

Does that track with your understanding?

johnbcoughlin··on How we could stumble into AI catastrophe
High net worth spending has a large opportunity cost. Of course some people are employed making yachts, but they could instead be employed in more useful productive enterprises. That is, wealth inequality generates a misallocation of the productive capacity of society. It's perfectly reasonable to oppose that.
johnbcoughlin··on Improving Async Networking in Python
What should it do when you call an async function from non-async? Block?
johnbcoughlin··on Subverting the software interview (2021)
> validate his code

> by Naomi Liu

johnbcoughlin··on Apple Rankings
Without having tried it... honeycrisp would be very likely to make a terrible apple pie due to too much water and sweetness.
johnbcoughlin··on What is an eigenvalue?
The speed of sound is the eigenvalue of a particular matrix (the "flux Jacobian") in the Euler equations, the 5-component system of partial differential equations that describe gas dynamics.
johnbcoughlin··on Tesla engineers were on-site to evaluate the Twitter staff’s code, workers said
> That would be well inside their domain.

Would it?

johnbcoughlin··on Turns are better than radians
One way to understand where the formulas come from is the power series of e^x, remembering that that function is (can be) defined as the function whose derivative is itself. Sin and cos are functions whose second derivative is -sin and -cos respectively. If you plug in ix to the power series for e^x, the complex exponential comes right out.

There are a couple other "paths" to this result, and the choice we have is by far the most elegant.

johnbcoughlin··on Korean nuclear fusion reactor achieves 100M°C for 30 seconds
The heat flux management from the plasma is certainly not dumb engineering, true. However, the actual heat transfer technology is, I think it's fair to say, "dumb" compared to all of the plasma physics that has to enable the reactor in the first place. It's more or less just running cold water through the lithium blanket, which they hope to keep under around 1000 Celsius or so.
johnbcoughlin··on Korean nuclear fusion reactor achieves 100M°C for 30 seconds
The heat transfer is not (will not be) directly from the plasma to the water. The fusion neutrons will impact a "blanket", which is water-cooled, and kept at a temperature of around 600-800 C. Weakening of the pipes and all other structural components will primarily be from neutron irradiation. Not to say that any of it's easy, just not for the reasons you suppose. :)
johnbcoughlin··on Superefficient solar desalination (2020)
Converting water to steam is an extremely inefficient way to separate water from salt.
johnbcoughlin··on Lessons I wish I had learned before I started teaching differential equations [pdf] (1997)
This is basically correct, the theory of distributions can be presented in terms of linear functionals. A functional is a map that takes a function and returns a scalar. I'm not sure how to encode linearity in your type system though...
johnbcoughlin··on The Trouble with the Segway (2009)
Well, walking is hard for many people of course, but for most of them, mounting and dismounting a Segway would seem to be almost as hard.
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