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jordibc

30 karma · joined October 28, 2015

Your friendly neighborhood astrophysicist.

Personal website: https://metamagical.org/

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jordibc··on Babashka 1.12.215: Revenge of the TUIs
Clojure is a fantastic language, but I have always missed a quick interactive shell where you can easily explore the language, using tab-completion and viewing the documentation easily in a way similar to ipython for the Python world. This release of Babashka fills beautifully that role for me.

I hope it shows and helps others start exploring with this beautiful language!

jordibc··on Writerdeck.org
I thought about it when I read Charlie Stross getting one last year [0]. Then thought, what is essential about it? And decided to try something related, even if it was likely to be just another distraction:

  (defun full-screen ()
    (interactive)
    (shell-command "wmctrl -r :ACTIVE: -btoggle,fullscreen")
    (menu-bar-mode 0))

  (defun just-write ()
    "Convert into a big, clean, centered window."
    (interactive)
    (full-screen) (olivetti-mode) (text-scale-adjust 2) (scroll-bar-mode -1)
    (end-of-buffer) (recenter-top-bottom 0))
This is the simple "just-write" function I wrote in emacs, and it also needs the olivetti package and the wmctrl program.

To my surprise, it actually did the trick. I've written more and more pleasantly since then. I feel it's better than if I had gotten a Writer Deck or similar. So I thought I'd share in case it does the trick for anyone else.

(I also use a font and a color scheme that pleases me, but that's minor.)

[0] https://www.antipope.org/charlie/blog-static/2024/09/zen-and...

jordibc··on A “knot dominated era” may have existed in the early universe: study
I think the idea of knots as a basis for everything has come and gone several times. One of those were in the 90s, which is when I became aware thanks to the excellent "Gauge Fields, Knots and Gravity" by John Baez and Javier P Muniain, that was part of the "Series on Knots and Everything" [1]. Those are really intriguing ideas.

[1] https://www.worldscientific.com/series/skae

jordibc··on Leaving Gmail for Mailbox.org
Convenience. It will be maintained for much longer. And I'm used to it by now.
jordibc··on Leaving Gmail for Mailbox.org
I found myself in a similar situation and also started de-googling, which is much nicer and liberating than I was fearing.

I did the exact same thing with Immich (what a great software, by the way!).

And in case it helps:

Instead of always relying on google maps, I now mostly use CoMaps (https://www.comaps.app/). Way better than using directly OpenStreetMap. And for my Pixel 7, I switched to LineageOS with gapps (https://lineageos.org/) and I'm not missing anything and am very happy with it.

Also, I'm trying now Nextcloud (https://nextcloud.com/), with a setup similar to Immich, and now I do believe there is life beyond google, and it's a better life.

jordibc··on Gemma 3 270M: Compact model for hyper-efficient AI
I suspect you are rather referencing Abbott & Costello's "Who's on First?" :) https://www.youtube.com/watch?v=2ZksQd2fC6Y
jordibc··on Firefox Browser Ported to HaikuOS
Thanks for clarifying! FWIW, I wasn't there, but that matches exactly what I remember from that time (I did follow all the different renamings in detail).
jordibc··on An intuitive guide to Maxwell's equations (2020)
Cool, I didn't know that. Still, the main point of the geometric algebra version is that it's not a "stitching" exercise, but a natural operation in the algebra -- and even better, an invertible one.
jordibc··on An intuitive guide to Maxwell's equations (2020)
Just to give a brief answer to those reasonable criticisms:

The mixed-grade already exists in complex numbers (it is very useful there, and even more so in geometric algebra).

Differential forms are included in geometric algebra (the exterior/outer products are isomorphic). Turns out, combining that product with the inner product gives you an invertible product (as Clifford found out). That by itself already is a huge advantage.

Finally, Maxwell's equations are sweetly summarized in differential forms, but even more in geometric algebra: dF = J . Not only it is just one equation instead of two, but in addition the "d" (or "nabla") is directly invertible thanks to the geometric product (which differential forms lack and then have to use more indirect methods, including the Hodge dual).

By the way, I'm very partial to geometric algebra, but wouldn't say it is an "error" not to use it! Maybe just a big missed opportunity :)

jordibc··on Rapier is a set of 2D and 3D physics engines written in Rust
Well, I got sucked down the same Geometric Algebra rabbit hole, plus another "remarkably concise and intuitive way" one too, which is Clojure.

So I wrote a library that can generate any GA and do all kind of fun operations (which could be used in particular as a basis for a physics engine). Just in case any of this is of your interest too: https://cljdoc.org/d/net.clojars.jordibc/geometric-algebra/

jordibc··on A Tour of the Lisps
It does preclude it, but clojure found an arguably elegant solution to it, using recur[1] instead. As a plus, in addition to achieving the same result as tail-call elimination, it does check that the call is indeed in tail position, and also works together with loop[2].

For me, it made me not miss tail-call elimination at all.

[1] https://clojuredocs.org/clojure.core/recur

[2] https://clojuredocs.org/clojure.core/loop

jordibc··on Simple Made Easy (2011) [video]
> (I just wish I understood what in meant in "Effective Programs" by "typos are not important". They are, aren't they ? A typo is a runtime error begging to occur during the demo, how is that "not important" ? Never mind.)

They are going to create an error that you can see and fix immediately, in the vast majority of cases. Certainly in compiled languages (like clojure), but less so in interpreted languages like python, where a misspelled variable in a hidden part of the code may not cause an exception until that part of the code is run.

At least, that's my understanding of what he means by typos being less important than other types of mistakes.

By the way, when I saw his comment originally I was surprised too. But when comparing to the other kind of mistakes he talks about I realized that, yes, I'd rather have a typo than any of the other problems! Though of course, I'd prefer to have none :)

jordibc··on jq 1.7
I really like jq, but I think there is at least one nice alternative to it: jet [1].

It is also a single executable, written in clojure and fast. Among other niceties, you don't have to learn any DSL in this case -- at least not if you already know clojure!

[1] https://github.com/borkdude/jet

jordibc··on KeePassXC Audit Report
I encrypt with gpg and upload the .xkdb file (itself already encrypted) to a server I have access to with scp.

Not manually, and not only for this file: this is a system I have to sync the files I want in different machines, by running a little program I wrote (https://gitlab.com/jordibc/csync just in case). I would use syncthing otherwise, but this system has several advantages for me.

If I hadn't access to an online server, I'd use some cloud storage for the same thing.

jordibc··on Ask HN: Math books that made you significantly better at math?
In case it helps:

In addition to "Geometric Algebra for Physicists" (whose first two chapters I'd recommend to get a nice overview), I found Hestenes' "New Foundations for Classical Mechanics" to be very good and readable.

Also, there are many good resources in https://bivector.net/ , including videos, papers, presentations and programs.

Finally, an interesting paper (that got me kickstarted) is "Imaginary Numbers Are Not Real—The Geometric Algebra of Spacetime" by Gull, Lasenby and Doran.

jordibc··on Ask HN: Math books that made you significantly better at math?
For sure I got significantly(?) better with classics like Spivak, Apostol, Rudin.

"Real and Complex Analysis" by Rudin, and the two books both named "Calculus" from Spivak and Apostol. But also from Apostol his more concise and far-reaching "Mathematical Analysis". And from Spivak his small gem "Calculus On Manifolds" made quite a dent on me.

Other than more "classic math" books, I also wanted to mention two outliers that I found eye-opening and generally awesome:

* Street-Fighting Mathematics, by Mahajan (http://streetfightingmath.com/). Intuitive, useful and fun.

* Geometric Algebra for Physicists, by Doran and Lasenby. I found the power and elegance of geometric algebra mesmerizing, and even if this book is also about physics and there may be more appropriate math-only books about geometric algebra, this is the one that made it for me.

jordibc··on VALL-E: Microsoft’s new zero-shot text-to-speech model
I think you mean https://github.com/neonbjb/tortoise-tts (missing last "s")
jordibc··on The end of the nice GTK button
About the USB keyboard, that may be true only for the cheapest keyboard you could find, but basically not applicable anymore nowadays. Rather than giving you the details, let me link to this video, which is awesome at explaining it and much more -- the USB vs PS/2 part starts here: https://www.youtube.com/watch?v=wdgULBpRoXk&t=1766s
jordibc··on Xsnow
Apologies to my old classmates at the university, when during the computer lab sessions I would telnet(!) to their machines and launch at random times xneko and/or xsnow. Seeing their surprised and puzzled reactions from a few rows behind was one of the best silly laughs I've had in my life!

(If you happen to be one of them, track me down, I'm thanking you for your inadvertent participation and will invite you to a well-deserved nice meal.)

jordibc··on ALiEn – a GPU-accelerated artificial life simulation program
Yes, cool dude indeed! Glad you mention him, I was thinking of him when I saw this article. He visited the group where I was doing my PhD many years ago and also gave a fantastic talk on evolution, learning, and artificial life -- I was quite impressed. He has some cool stuff in his website too (http://shinyverse.org/larryy/).
jordibc··on Statement by Jill Bähring Regarding Jacob Appelbaum
Any idea of why it has been flagged?

Were the ones that spread suspicion about Appelbaum flagged too? It looks to me as this would be quite relevant news.