PySCF by Ciro Santilli 35 Updated +Created
Priory 600ADX by Ciro Santilli 35 Updated +Created
pyBullet by Ciro Santilli 35 Updated +Created
Became very popular as of result of people using Bullet Physics for reinforcement learning AI training robot simulations.
Source code: somewhere inside the main Bullet Physics source tree. Yay.
Pu Songling by Ciro Santilli 35 Updated +Created
Sometimes you just know that your existence will be remembered for a singular reason. Better than not being remembered at all perhaps.
Paper by Philip W. Anderson and John M. Rowell that first (?) experimentally observed the Josephson effect.
TODO understand the graphs in detail.
They used tin-oxide-lead tunnel at 1.5 K. TODO oxide of what? Why two different metals? They say that both films are 200 nm thick, so maybe it is:
   -----+------+------+-----
...  Sn | SnO2 | PbO2 | Pb  ...
   -----+------+------------
          100nm 100nm
A reconstruction of their circuit in Ciro's ASCII art circuit diagram notation TODO:
DC---R_10---X---G
There are not details of the physical construction of course. Reproducibility lol.
Theme music by Ciro Santilli 35 Updated +Created
Title sequence by Ciro Santilli 35 Updated +Created
Television series by Ciro Santilli 35 Updated +Created
Performing arts by Ciro Santilli 35 Updated +Created
Punycode inscription by Ciro Santilli 35 Updated +Created
Namecoin examples are catalogued at: punycodes.xyz. The are small Unicode art or emoji code.
There seems to be nothing of particular artistic value as far as we've seen so far, the only interest in such tokens seems to be that:
Cuisine by region by Ciro Santilli 35 Updated +Created
Punched card by Ciro Santilli 35 Updated +Created
Served as both input, output and storage system in the eary days!
Video 1.
1964 IBM 029 Keypunch Card Punching Demonstration by CuriousMarc (2014)
Source.
Video 2.
Using Punch Cards by Bubbles Whiting (2016)
Source. Interview at the The Centre for Computing History.
Video 3.
Once Upon A Punched Card by IBM (1964)
Source. Goes on and on a bit too long. But cool still.
ASCII porn by Ciro Santilli 35 Updated +Created
Collections and overviews:
You just couldn't resist Googling it and clicking this page, could you? You naughty, naughty bearded programmer nerd. Yes, I'm talking to you.
TODO it is quite hard to actually find non-automatically generated ASCII art of people fucking, most of them are just sexy/horny women drawn by bearded nerds, likely and based on sticky physical paper porn magazines from the 80's, good old days.
                                    |
                                    |
   Tank Man                         |
   by Ciro Santilli          00     |
   2021 CC-BY-SA 4.0          \\  +-|-+
                               \\/   /|-+o
                                \\--+ / /o
                               /|\\ |/ /oo
                        |     / ----- /oo
                        |    /       /oo
                        |   +-------+oo
                        |   oo+---+ooo
                 00     |   oo     oo
                  \\  +-|-+
                   \\/   /|-+o
                    \\--+ / /o
                   /|\\ |/ /oo
            |     / ----- /oo
            |    /       /oo
            |   +-------+oo
            |   oo+---+ooo
     00     |   oo     oo
      \\  +-|-+
       \\/   /|-+o
        \\--+ / /o
       /|\\ |/ /oo
      / ----- /oo
     /       /oo
    +-------+oo
    oo+---+ooo
    oo     oo
 xx
 --
/||\
|--|
o||0
 ||
 /\
ASCII typeface by Ciro Santilli 35 Updated +Created
Tis term was invented by Ciro Santilli, it refers to ASCII art of text, essentially creating a typeface. in that medium..
Art trend by Ciro Santilli 35 Updated +Created
Games young Ciro Santilli played by Ciro Santilli 35 Updated +Created
Mostly video games of course.
First when he was really young, about 5, Ciro played a lot of NES, but he doesn't remember things from that era very well. Contra, Ninja Turtles, Battle Tanks, Duck Hunt, and some modern "real world jet" top to bottom rail shooter (TODO identify) are definitely some of the games he clearly remembers playing, see also: Figure "Five year old Ciro Santilli playing NES on a joystick". Nintendo hard was truly a thing back then.
As an honorable mention, Ciro remembers his teenage/young adult neighbours in Jundiaí playing some DOS games on their computer, notably there was a 3D racing one. This must have been around 1995/1997, so using some of the very earliest GPUs. Those games felt so incredibly advanced, including the required setup to play them, which required some command-line commands. It felt like some kind of black magic! But Ciro didn't really play them however.
Ciro then skipped the SNES and handhelds, which he played only through friends because he was cheap (but also because Brazil is a poor country remember, and imports are pretty expensive). He clearly remembers playing Super Mario World for the SNES and Pokemon on friends' Gameboys of course.
Ciro then went straight to 5th generation with the Nintendo 64 in 1994 which his parents bought for him during a trip to the United States. Once again, because he was cheap, the only game he bought was Super Mario 64, which likely came with the console? He played that game to death.
Then came Ocarina of Time, which blew everyone's minds, and Ciro would go to Blockbuster to rent it for the weekend, and again play to death with his friends. You had to arrive early at Blockbuster to rent it, otherwise other people would rent all copies!!!
The only time Ciro got robbed as of 2020 was when an older teenager stopped his bicycle in front of Ciro and took his rented Golden Eye 64 copy away from his hand, and run off. Poor drug addict.
Ciro always felt that the PS1 had a much uglier aesthetics than the N64, and didn't like the console. Playing a bit of Final Fantasy VI on his memory did stick deeply to his mind however. Ciro later played all good PS1 RPGs on emulation during University of São Paulo during amazing solitary nights.
And on the PC, Ciro was particularly touched by Age of Empires II and Diablo II.
As a young teenager Ciro would also play Counter-Strike with his friends at LAN houses. Playing that game would make Ciro extremely anxious, his hands got all cold, and it was a lot of fun.
After this Ciro grew up and notice that the only fun game is that of becoming become rich and famous in the real world.
This explains however Ciro's tool-assisted speedrun interests.
Outside of video games, Ciro got midly addicted to Magic: The Gathering in his early teens.
Principal component analysis by Ciro Santilli 35 Updated +Created
Given a bunch of points in dimensions, PCA maps those points to a new dimensional space with .
is a hyperparameter, and are common choices when doing dataset exploration, as they can be easily visualized on a planar plot.
The mapping is done by projecting all points to a dimensional hyperplane. PCA is an algorithm for choosing this hyperplane and the coordinate system within this hyperplane.
The hyperplane choice is done as follows:
  • the hyperplane will have origin at the mean point
  • the first axis is picked along the direction of greatest variance, i.e. where points are the most spread out.
    Intuitively, if we pick an axis of small variation, that would be bad, because all the points are very close to one another on that axis, so it doesn't contain as much information that helps us differentiate the points.
  • then we pick a second axis, orthogonal to the first one, and on the direction of second largest variance
  • and so on until orthogonal axes are taken
www.sartorius.com/en/knowledge/science-snippets/what-is-principal-component-analysis-pca-and-how-it-is-used-507186 provides an OK-ish example with a concrete context. In there, each point is a country, and the input data is the consumption of different kinds of foods per year, e.g.:
  • flour
  • dry codfish
  • olive oil
  • sausage
so in this example, we would have input points in 4D.
The question is then: we want to be able to identify the country by what they eat.
Suppose that every country consumes the same amount of flour every year. Then, that number doesn't tell us much about which country each point represents (has the least variance), and the first PCA axes would basically never point anywhere near that direction.
Another cool thing is that PCA seems to automatically account for linear dependencies in the data, so it skips selecting highly correlated axes multiple times. For example, suppose that dry codfish and olive oil consumption are very high in Portugal and Spain, but very low in Germany and Poland. Therefore, the variation is very high in those two parameters, and contains a lot of information.
However, suppose that dry codfish consumption is also directly proportional to olive oil consumption. Because of this, it would be kind of wasteful if we selected:
since the information about codfish already tells us the olive oil. PCA apparently recognizes this, and instead picks the first axis at a 45 degree angle to both dry codfish and olive oil, and then moves on to something else for the second axis.
We can see that much like the rest of machine learning, PCA can be seen as a form of compression.
Cf. by Ciro Santilli 35 Updated +Created
Greek root by Ciro Santilli 35 Updated +Created
Art young Ciro Santilli consumed by Ciro Santilli 35 Updated +Created
Maybe those are genial. Maybe not. Nostalgia is just too strong to discern. Ciro still goes back to them for rest.

Pinned article: ourbigbook/introduction-to-the-ourbigbook-project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
We have two killer features:
  1. topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculus
    Articles of different users are sorted by upvote within each article page. This feature is a bit like:
    • a Wikipedia where each user can have their own version of each article
    • a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
    This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
    Figure 1.
    Screenshot of the "Derivative" topic page
    . View it live at: ourbigbook.com/go/topic/derivative
  2. local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:
    This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
    Figure 5. . You can also edit articles on the Web editor without installing anything locally.
    Video 3.
    Edit locally and publish demo
    . Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
  4. Infinitely deep tables of contents:
    Figure 6.
    Dynamic article tree with infinitely deep table of contents
    .
    Descendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact