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Diary, February 2022

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 20  21  22  23  24  25  26
 27  28

Tuesday, February 1, 2022


Today is the first day of the year 4719, the year of the tiger according to the Chinese calendar. The spring festival has begun.

Wednesday, February 2, 2022

Palindrome date

Today is a palindrome date when written according to the D(D)-M(M)-YY format: 2-2-22 and the YY.(M)M.(D)D formats: 22.2.2. The previous such date was January 22.

Saturday, February 5, 2022

Sex at Dawn

I finished reading the book Sex at Dawn: How We Mate, Why We Stray, and What It Means for Modern Relationships, which I started reading on January 28, two days after I bought the book. The TED talk by Christopher Ryan Are we designed to be sexual omnivores? give a good summary of the book. I found the first chapter of the books rather rethoric. The book makes some good arguments, but I think the truth is a bit more complicated and there are other solutions to the problems that the authors address. I think that the main reason is that we have a larger brain than the apes we are closely related to. Anyhow, it was an interesting read.

Sunday, February 6, 2022

Room to Dream

I finished reading the book Room to Dream by David Lynch and Kristine McKenna, which I started reading on October 21 last year after I bought it exactly a month earlier. The interesting fact about this book that it is both a biography and an autobiograph. There are alternating chapters where McKenna writes a biographic chapter (based on her research) followed by an autobiographic chapter where Lynch writes about his recollections after reading the chapter. Sometimes there are things he cannot remember, at other points he adds some of his own unique points of view to it. It is really a refreshing concept, the 'objective' story mirrored with the 'subjective' story. I found the latter part of the book getting a bit long-winded and a bit too much focussing on the works of Lynch and less on his personal life. But yes, it is clear that his life is very much about his work and that several of his marriages have died out due to him being engrossed in his work project. I have not been a great fan of Lynch and not seen many of his films and series, but is has raised my interest in watching them.

Monday, February 7, 2022

Documenta books

At 17:35:41, I bought two sets of books related to Documenta the book from bookshop Broekhuis. The first set, written in German and English, and published by Taschen in 2007, I bought for € 15.00. It consists of: The second set, published by Cantz in 1997, I bought for € 24.50. It consists of:

Wednesday, February 9, 2022

Sequential circuits

Yesterday, I saw this tweet with the text sequential circuits with an interesting image attached to it. I immediately thought about how many there are for any given size. While we were walking, I figured out that the number must be n!(n-1)!/2 (The OEIS sequence A010796.) In the evening, I searched for the tweet, but could not find it. I did write a small JavaScript program to generate them. But they looked rather different from what I remembered. Today, I found the tweet again and it confirmed my impression that they look different. I have been thinking about how to generate more similar looking sequential circuists, but I have not come up with a good idea. The results of the program I wrote yesterday are displayed below. (I added some code to generate a new one every two seconds.)

This text is displayed if your browser does not support HTML5 Canvas.

Friday, February 11, 2022


At 17:41, I bought a slipcase the book Qua Art Qua Science 2004-2008 (publised in 2008) and Qua Art Qua Science 2009-2013 (published in 2014) edited by Martha J. Haveman, written in Dutch and English, and published by Foundation Qua Art-Qua Science from charity shop Het Goed for € 5.95.

Sunday, February 13, 2022

Covid-19 scenarios

It is now becoming clear (through requests based on the Dutch Freedom of Information Act) that some people in the Dutch National Institute for Public Health and the Environment (RIVM) already in February 2020 considered that COVID-19 could have a large impact. On February 9, one of the researchers of the a newly established "response team", which is trying to estimate the consequences of the corona virus for the Netherlands, wrote in an email to his bosses: "The impact of an nCoV epidemic is classified as a serious to catastrophic threat to national security." For the risc analyses they made use of Leidraad risicobeoordeling; Geïntegreerde risicoanalyse Nationale Veiligheid (Guidance risk assessment; Integrated risk analysis National Security, in which 'catastrophic' stands for more than 10,000 casualties. Again, on February 13, there is an internal email stating: "Worst case scenario: 6x worse than seasonal influenza in terms of deaths." However, a week later on February 20, Jaap van Dissel does not say anything about this during a technical briefing at the Dutch House of Representatives. In another email from February 6 states that there is proof of transmission before the first day of illness and there are indications that more than half of the infections occur before that day. For a long time, the government denied that this could happen and at the end of February, the conservative-liberal party denounced unnecessary parliamentary questions and assumptions about this. The RIVM now states that these were scenarios not predictions.

Hengelo LICHT

In the evening, Conny and I went to Hengelo to look at the (mini) light festival, called LICHT (Dutch for light). There we saw the installations:

Wednesday, February 16, 2022

eqn versus Tex

Yesterday, Lorinda Cherry was found death in her home. She was a computer scientist and programmer who worked at Bell Labs. Together with Brian Kernighan she developed eqn, a preprocessor that formats equations for printing. Itis similar to the mathematical component of TeX developed by D.E. Knuth, which appeared several years later. The paper A System for Typesetting Mathematics starts with the example:
  sum from i=0 to infinity x sub i = pi over 2
The following describe the same mathematical expression in TeX:
  \sum_{i=0}^{\infty} x_i = {\pi \over 2}
I somehow feel it is a pitty that Knuth went on to design his own method for describing mathematical expressions, as his seems to less semantic and more based on representation. Note how in his notation the two '_' have a total different semantic meaning, while in eqn different syntax is used. His method is a more consize, but even not that much, but her method is much closer to how the resulting expression is read. I did have a look at the paper mentioned and noted that terms like 'sub' and 'sup' are also related to position. An even more semantic approach probably would use 'x power 2' instead of 'x sup 2'. I wondered whether it would be possible to write a preprocessor to replace a more eqn like syntax to the TeX syntax. When I searched for a grammar for TeX, I across: Is there a BNF grammar of the TeX language?, which explains that parsing TeX is Turing complete due to the fact that TeX itself is Turing complete and use this to adapt the input processing depending on this. It is not strange that TeX is Turing complete, because it is basically a programming language. But it is not a very well defined programming language because its syntax is rather complex and it is possible to redefine symbols while processing the input.

Saturday, February 19, 2022


This afternoon, I saw two exhibitions when I was in town. The first was at Concordia: Inkspot 2021 with a selection of the best political cartoons that appeared in Dutch newspapers. Many of these are without words and about world events. This year winner was Luc Zeebroek, better known as Kamagurka. The second was the exhibtion Madonnas by Hanna Jansen at Fotogalerie Objektief. Quite intriguing, because the pictures are about adult couples.

Tuesday, February 22, 2022

Palindrome date

Today is a palindromedate when written like 22/02/2022 (DD-MM-YYYY), 22-2-22 (DD-M-YY), and 22.2.22 (YY.M.DD). It is also a "Digital" rotation dates rotation date for all these formats. The third such date for the DD-MM-YYYY format.

Wednesday, February 23, 2022

Dune 2021 scipt

In the evening, I read (skimmed) through the Dune 2021 script dated September 24, 2018 with the idea in mind to compare it with the Dune screenplay (dated June 19, 2020). The final screenplay seems to be very close to the transcript of the movie. I made some notes about the scenes but did not make a details analyses. I also wanted to compare it to the list of deleted scenes. My first impression that the greatest differences between this script and the screenplay are that the start and the end of the movie. I had expected to find the deleted scenes in this script, but they were not all there. I also noted that also in this script, the whole sub-plot of a traitor is missing.

Sunday, February 27, 2022


In the afternoon, I went to see the exhibition Eyebright by Hannelot van Elst at TETEM art space. I found the pictures impresive, also because of the combination with stylistic pictures of dead flowers. In June 2018, I saw work from her at the exhibition Under Sweet Surveillance.

This months interesting links

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