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#triangle

5 posts5 participants1 post today
Public
nosfe

I have Fujichrome R25 Single-8 8mm film on which one of the color layers has spontaneously formed #Sierpinski #triangle #fractal like patterns, all over the whole 15m roll.

It is unclear if this has happened through some biological or physical process, and would like some help finding out.

Public
Ross Grady

TL;DR: If you live in the #Triangle area of NC and you are interested in live music:

http://roks.me

So: For ~22 years or so I ran a website called trianglerock.com which aggregated show listings for venues around central NC (primarily #Raleigh, #Durham, #ChapelHill).

It started out entirely manually assembled, and I gradually automated portions of it. But for ~reasons~, namely:

  • I intentionally wanted each band/artist, and each venue, to be an entity in a database, so that it could be searchable later (via a search interface I never finished building)
  • I was a completist & that meant seeking out show listings in social media & other non-scrape-able places
  • I didn’t list everything, and for shows I personally cared about, I included some preview verbiage I wrote myself

it always required a few hours a week of manual labor.

When the pandemic hit & all the venues shut down, I sort of belatedly reached the conclusion that I was tired of spending a few hours a week on it . . . so I never started it back up again after venues started re-opening.

(I also don’t go out to many rockclub shows anymore, because too many of the rockclubs around here (with a handful of exceptions, thank you, you know who you are) are depressing black-painted concrete-floored boxes with zero character, disgusting bathrooms, and noplace to sit.)

A few times over the past few years, people have mentioned to me that they missed the site (including multiple venue owners / bookers / promoters) but my careabout number remained super-low.

A couple of weeks ago, though, I was at a show, seeing an amazing band from Toronto called The Weather Station, and chatting with a few old friends. Two topics came up multiple times:

  • our mutual surprise that there weren’t more people there
  • my old friends’ characterization of me, when introducing me to their kids / partners, as “umm, how do I explain Ross? Well, he used to run this website . . . “

Partly I was like “dude I am standing RIGHT HERE you don’t have to past-tense me like that” but also in talking to them they did genuinely bemoan the difficulty in keeping track of shows since I quit.

I still don’t want to spend any significant amount of time collating show listings.

But nearly all the venue websites these days are using some kind of WordPress plugin or other framework that generates predictably-structured HTML. I had already written parsers for a few of them back in ~2018 or so . . . so it wasn’t much effort at all to expand my parser collection.

The result is a minimal static site that is just a date-sorted aggregation of all the listings I can scrape: http://roks.me

(Yeah, http – I don’t feel like doing even the minimal LetsEncrypt dance here, and if ppl are worried that a static html site is too risky to load via http then they probably aren’t leaving their houses to go to rock clubs either.)

One thing that amused me & also made me feel old was realizing that ~5 years off the local-music beat also means that I couldn’t write blurbs about most of these shows even if I wanted to, not without doing a LOT of research . . . and I’m not particularly interested in diving back into the world of one million indie-rock and garage bands who are all great people and write decent songs but are also, ahem, very similar to 7000 other indie-rock and garage bands I have personally seen over the past 40 years of going to shows.

roks.meroks.me
Public
Dani Laura (they/she/he)

I have found an interesting geometric fact: suppose you have a hexagon of side 1 and duplicate and enlarge it by the golden ratio 𝜑; the distance from one vertex of the unit hexagon to a vertex of the bigger hexagon 60° apart is √2. Furthermore, if another hexagon reduced by 𝜑 is drawn inside, the distance from one vertex of the unit hexagon to a vertex of the smaller hexagon 120° apart is also √2 [first figure].
This boils down to the fact that a triangle of sides 1, √2, and 𝜑 has an angle of 60° opposite to side √2. That triangle is very remarkable as it contains the three more relevant algebraic geometric constants: √2, √3/2 (altitude to the bigger side) and 𝜑 [second figure]. Of course this can be also used to construct 𝜑 from a square and a triangle (I bet this is known). In the follow-up some artistic designs exploiting those facts.

Three concentric hexagons, see post for details.
Triangle of sides 1, √2, and 𝜑, and altitude √3/2.
Public
Reverend Elvis

New series: Underestimated instruments. The triangle.
In our beautiful house, with its 22-year history that it has experienced with us, there is something to discover around every corner. It is a great treasure trove for music, art and rock ‘n’ roll. We are trying to preserve it, as you know. Important things would be lost, such as our triangle collection. A good friend of ours, who works as a carpenter at the municipal opera, has given us old percussion instruments from his family’s estate. We are not a museum, so we use it; you have heard some of the things on my records.
Now our long-forgotten triangle collection has turned up. Anyone who has seen a symphony orchestra knows that it is quite an important instrument and not just something played in kindergarten. These are tuned triangles for professional use. So, for those who have not yet learned an instrument, there is hope.
word.undead-network.de/2025/04
#instruments #culture #art #music #triangle #undead

Public
Cahiers Pédagogiques

[ARTICLE EN ACCÈS LIBRE]
Pourquoi l’explicitation est-elle essentielle en classe ? Par Julie Lefort
Si l’idée tenace d’imposer un « enseignement explicite » provoque des résistances en France, au Canada ou en Belgique, il existe, par ailleurs, des raisons impérieuses d’expliciter les attendus d’apprentissage auprès des élèves. Voici un exemple précis et précieux pour l’enseignement du théorème de Thalès avec des élèves en 4e.

#maths #collège #explicitation #enseignementexplicite #Thalès #triangle

⬇️ ⬇️
cahiers-pedagogiques.com/pourq

Les Cahiers pédagogiques · Pourquoi l’explicitation est-elle essentielle en classe ? - Les Cahiers pédagogiquesComment l’explicitation en classe aide les élèves à structurer et verbaliser leur pensée et à mieux comprendre le raisonnement mathématique.
Public
Dani Laura (they/she/he)

Some based in triangles. The idea is to start with a set of triangles connected by their sides, and iteratively selecting the larger side in the set and dividing it using a simple definite rule (I don't use randomness). Stop when all sides are less than a given value. Using the research pointed out in my previous post, each triangle is assigned a colour just based on its shape.

#triangle#geometry#Mathematics
Public
Dani Laura (they/she/he)

In my research for new , I have developed a nice chart to show the different types of triangles that exist (1). The idea was to classify them by how they look visually. The chart starts from a horizontal segment which will be the largest side of the triangle (or one of the larger). Then each point of the chart represents the triangle formed by joining that point to the ends of the segment (in fact if we are not interested in distinguish chirality half of the chart would suffice, but I find aesthetically nicer the symmetric version). By looking at it I have realized that isosceles triangles can be split into two visually different types: pointed and squashed. In pointed isosceles triangles the different side is smaller than the other, in squashed ones the opposite. Of course obtuse and right isosceles triangles are always squashed. The second image is what you obtain if the initial side is not necessarily the largest (colour codes are the same).

(1) Which is not new, I have found something similar in Hebrew: commons.m.wikimedia.org/wiki/F
By the way, it would be nice if someone could develop an image search which understand 2D geometry.

#Maths#Mathematics#triangle
Public
WordofTheHour

#triangle : a figure bounded by three lines, and containing three angles

- French: triangle

- German: das Dreieck

- Italian: triangolo

- Portuguese: triângulo

- Spanish: triángulo

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