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Reminds me of friends who got under the thrall of a[n explicitly] religious cult. You can’t reason them out of it, because their faculties of reason have been short-circuited by the linguistic circularity of the cult. You can’t appeal to what should be their reluctance to cause distress to the people who care about them, because their hearts belong to the cult now. You just need to wait and see if they snap out of it. They often do, and it’s surprising.

Perhaps cult deprogramming techniques can help woke people. I don’t know anything about them, but it’s worth looking in to .


My argument: The Prisoner.

All of the light ray diagrams in the article are incorrect.

Can you please elaborate? I couldn't figure out what was incorrect in them

Not sure which aspect the earlier post meant but the rays are only refracting on the exit surface, when of course they also refract on the entry surface.

That’s it.

You don’t need an extension. You can just use the `-site` operator, and put your list in a bookmarklet, or use your browser’s ability to define search shortcuts, if it has that.

Until Google starts ignoring that operator. Or the next blogspam SEO site pops up that's not on your -site list.

Not only does the page explain what you see, but it refers to the feather-bowling ball demonstration that was filmed on the Moon.

It does! However, when I scroll to the bottom of the page I only see the title of that section, not the explanation, nor the accompanying video.

I didn't realize the "Why balls fall at all" was a button.


If anyone wants to play around with this old-school, here's a text based Python script that drops various things simultaneously and prints a table of position and velocity over time relative to the starting point. https://pastebin.com/q1NGv71W

Predefined things you can drop are basketball, bowling_ball, massive_sphere, dense_sphere, lead_sphere, pine_sphere, pingpong_ball, ant, rat, cat, person, and phone. You can add other things if you know their mass, cross sectional area, and coefficient of drag.


The Julia REPL starts in less than a second, importing the Plots module takes a couple of seconds, and the first plot appears in a few more seconds (on my weak computer). If you keep the REPL open, subsequent plots are quite speedy. This may indeed not be snappy enough for some workflows that involve starting a fresh Julia process for each iteration—in which case, it’s pretty simple to create a sysimage with the plotting functions and anything else you use routinely precompiled in: https://www.matecdev.com/posts/julia-package-compiler.html

For concrete numbers, here's my experience on a super-crappy laptop:

* `add Plots` on a new temp environment takes about four and a half minutes, most of which is precompilation.

* `using Plots` took 16 seconds, and

* a `plot` call after that is 7 seconds.

For comparison, on 1.6, the times are seven and a half minutes for precompilation, 17 seconds for `using` and 10 seconds for the first `plot`. I'm not patient/masochistic enough to try the same on 1.5 too, but the trend is definitely one of continuous improvement.

This is certainly not the sort of machine any production Julia code will be run in, but it is in the category of machines that a lot of students and many others trying out the language will have access to, so it gives an idea of their experience.

The times on 1.6 and 1.7 have been a qualitative change for me. plot being sub-10 seconds means that instead of it being "run it, switch to something else while I wait (potentially losing my mental context), come back and hope it's done", it's now "run it, stare at my dog for a few seconds, the plot is ready".


My dog loves Plots.jl

I think it depends on the version of Julia the OP was using. If you're using 1.6/1.7 then startup and time to first plot are vastly improved. Earlier versions are quite a bit slower. There's been a lot of improvements in these areas in recent releases.

Quite right. Since I’ve been keeping track, at about v1.5, there has been significant speedup with every release.

That's true, though they said "recently".

I don't think time to first plot is that bad anymore.

Time to first gradient can be bad in Zygote/Flux.


One of the best comments ever.

I like these somewhat crazy ideas. You could get some of this behavior with macros in Julia, probably.

Julia lets you write `3x` for `3 * x` because it’s unambiguous, since variables may not start with numerals, but `ax` is not `a * x`, because `ax` is a legal identifier.

Exactly. Just without the comments.

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