Computer Science/Engineering Masterpost

1984

George Orwell

Idempotence.

A term I’d always found intriguing, mostly because it’s such an unusual word. It’s a concept from mathematics and computer science but can be applied more generally—not that it often is. Basically, it’s an operation that, no matter how many times you do it, you’ll still get the same result, at least without doing other operations in between. A classic example would be view_your_bank_balance being idempotent, and withdraw_1000 not being idempotent.

HTs: @aidmcg and Ewan Silver who kept saying it

+heroes of nusantara: multatuli

YES, I, Multatuli, “who have suffered much,”—I take the pen. I do not make any excuses for the form of my book,—that form was thought proper to obtain my object…. I will be read! Yes, I will be read. I will be read by statesmen who are obliged to pay attention to the signs of the times; by men of letters, who must also look into the book of which so many bad things are said; by merchants, who have an interest in the coffee auctions; by lady’s-maids, who read me for a few farthings; by governors-general in retirement; by ministers who have something to do; by the lackeys of these Excellencies; by mutes, who, more majorum, will say that I attack God Almighty, when I attack only the god which they made according to their own image; by the members of the representative chambers, who must know what happens in the extensive possessions over the sea which belong to Holland….  

Ay, I shall be read!

Eduard Douwes Dekker was born in Amsterdam, March 2nd 1820. His father was a ship’s captain and intended for his son to have a career in trade. This humdrum prospect disgusted Douwes Dekker and in 1838 he obtained a post as a civil servant on the island of Java. During the period between 1848 and 1851 Douwes Dekker eventually rose to serve as assistant resident in various regencies in the Indonesian archipelago including Natal, North Sumatra, Manado in Sulawesi and Ambon in the Moluccas. In 1857 he was transferred to Lebak, in the Bantam residency of Java (now Banten province). By this time, however, all the secrets of Dutch administration were known to him, and he had begun to openly protest about the abuses of the colonial system. Consequently, he was threatened with dismissal from his office for his openness of speech. Douwes Dekker resigned his appointment and returned to the Netherlands.

He was determined to expose in detail the scandals he had witnessed, and he began to do so in newspaper articles and pamphlets. Little notice, however, was taken of his protestations until, in 1860, he published his novel Max Havelaar under the pseudonym of Multatuli. Douwes Dekker’s new pseudonym, which is derived from Latin, means, “I have suffered much”, or, more literally “I have borne much” referring to himself, as well as, it is thought, to the victims of the injustices he saw. An attempt was made to suppress the inflammatory book, but in vain; it was read all over Europe. Apologists for colonialism accused Douwes Dekker’s horrific depictions of being exaggerated.

[ his statue in amsterdam ]

Although it was translated into English in 1868, the text wasn’t available in the author’s home country until over a century later in 1972. Collectively, Multatuli’s Max Havelaar has been translated into 34 different languages worldwide since its initial publication. Credited as the stirring initiation of the nationalist movement responsible for the termination of Dutch colonization of Indonesia following World War II, Max Havelaar’s legacy is not confined to literary accomplishment, but can be considered a work of great political success and inspired social liberation. Max Havelaar’s influence on the national movement ultimately culminated in the passionate command to end decolonization worldwide. The story of Max Havelaar illuminates the inhumane and political injustices brutally imposed upon the native peoples of the region.

Sigmund Freud listed Multatuli as one of his favorite writers. Multatuli’s brother, Jan Douwes Dekker, was the grandfather of Ernest Douwes Dekker (also known as Danudirja Setiabudi, a National Hero of Indonesia). There is a museum for him in Amsterdam. Multatuli is also known as the person who coined the term emerald of equator, a poetic nickname of Indonesia.

This book is an introduction….  I shall increase in strength and sharpness of weapons, according as it may be necessary.    Heaven grant that it may not be necessary!…    No, it will not be necessary! For it is to thee I dedicate my book: WILLIAM THE THIRD, King, Grand Duke, Prince,… more than Prince, Grand Duke, and King,… EMPEROR of the magnificent empire of INSULIND, which winds about the equator like a garland of emeralds!…    I ask THEE if it be thine IMPERIAL will that the Havelaars should be bespattered with the mud of Slymerings and Drystubbles; and that thy more than thirty millions of SUBJECTS far away should be ill treated and should suffer extortion in THY name!

source: wikipedia; culture trip

quotes from bartleby, excerpt of max havelaar

further reading: paper on multatuli

The math trick that college will never teach you! : Parametric Integration

Parametric integration is one such technique that once you are made aware of it, you will never for the love of god forget it. It goes by many names : ‘Differentiation under the Integral sign’, ‘Feynman’s famous trick’ , ‘Parametric Integration’ and so on.

Let me demonstrate :

Now this integral might seem familiar to you if you have taken a calculus course before and to evaluate it is rather simple as well.

Knowing this you can do lots of crazy stuff. Lets differentiate this expression wrt to the parameter in the integral – s (Hence the name parametric integration ). i.e 

Look at that, by simple differentiation we have obtained the expression for another integral. How cool is that! It gets even better.

Lets differentiate it once more: 

.

.

.

If you keep on differentiating the expression n times, one gets this : 

Now substituting the value of s to be 1, we obtain the following integral expression for the factorial. This is known as the gamma function.

There are lots of ways to derive the above expression for the gamma function, but parametric integration is in my opinion the most subtle way to arrive at it. :D

This is a really powerful technique and I strong suggest that if you have taken calculus, then please do read this article.

Have a great day!

EDIT:  It had to be gamma(n+1) not gamma(n) .Thank you @mattchelldavis

Check out this 1890s advertisement for cowpox vaccines sold by Lancaster County Vaccine Farms. The advertisement was published as part of the 1893 volume of Polk’s Medical and Surgical Register of the United States.

Word of the Day: potlatch

n. An opulent ceremonial feast (among certain North American Indian peoples of the north-west coast) at which possessions are given away or destroyed to display wealth or enhance prestige

Image: “Klallam people at Port Townsend” by James Gilchrist Swan. Public Domain via Wikimedia Commons

Since 2009, Ada Lovelace Day has aimed “to raise the profile of women in science, technology, engineering and maths by encouraging people around the world to talk about the women whose work they admire.”  The day’s namesake, Ada Lovelace (1815-1852), was the daughter of Lord Byron and Anne Isabella Milbanke.  Ada, in possession of a keen intellect and deep passion for machinery, was educated in mathematics at the insistence of her mother. Later in life, Ada studied the workings of the Analytical Engine developed by mathematician and inventor Charles Babbage. In her notes on the engine, Ada described an algorithm for computing numbers – an algorithm which would distinguish Ada as one of the world’s “first computer programmers.”  

In honor of Ada Lovelace Day, we present some images from the CHF Archives of women working in various chemistry labs. Click on each photo for additional information.

And for more women in science content, consider taking a look at the films in The Catalyst Series: Women in Chemistry by the Chemical Heritage Foundation.

Why do men have Adam's apples. It's so sexy but seems so unnecessary

It basically is unnecessary lol

It’s not that only men have Adam’s apples, women do too, but it’s less prominent. An Adam’s apple is just a piece of cartilage that protects your larynx (the voicebox) directly behind it. As boys & girls go through puberty, our voicebox grows which:

1. Causes our voice to deepen 2. Pushes the cartilage further forwards

In boys, the larynx grows in size significantly more which therefore pushes forward the evident bump of cartilage we like to call an Adam’s Apple.

Too much sex causes genitals to change shape, beetle study shows

Sexual conflict between males and females can lead to changes in the shape of their genitals, according to research on burying beetles by scientists at the University of Exeter.

The study, published in the journal Evolution, provides new evidence that conflict over how often mating takes place can lead to males evolving longer penis-like organs and females larger ‘claws’ on their genitalia, within ten generations.

“Our research demonstrates the general importance of conflicts of interest between males and females in helping to generate some of the biodiversity that we see in the natural world. It’s fascinating how genital evolution can happen so fast – in ten generations – showing how rapidly evolutionary changes can occur.”

Paul E. Hopwood, Megan L. Head, Eleanor J. Jordan, Mauricio J. Carter, Emma Davey, Allen J. Moore, Nick J. Royle. Selection on an antagonistic behavioral trait can drive rapid genital coevolution in the burying beetle,Nicrophorus vespilloides. Evolution, 2016; DOI: 10.1111/evo.12938

The Okinawan Language

Anybody who has studied Japanese and Linguistics will know that Japanese is a part of the Japonic language family. For many years it was thought that Japanese was a language isolate, unrelated to any other language (Although there is some debate as to whether or not Japanese and Korean are related). Today, most linguists are in agreement that Japanese is not an isolate. The Japonic languages are split into two groups: Japanese (日本語) and its dialects, which range from standard Eastern Japanese (東日本方言) to the various dialects found on Kyūshū (九州日本方言), which are, different, to say the least. The Ryukyuan Languages (琉球語派). Which are further subdivided into Northern and Southern Ryukyuan languages. Okinawan is classified as a Northern Ryukyuan Languages. There are a total of 6 Ryukyuan languages, each with its own dialects. The Ryukyuan languages exist on a continuum, somebody who speaks Okinawan will have a more difficult time understanding the Yonaguni Language, which is spoken on Japan’s southernmost populated island. Japanese and Okinawan (I am using the Naha dialect of Okinawan because it was the standard language of the Ryukyu Kingdom), are not intelligible. Calling Okinawan a dialect of Japanese is akin to calling Dutch a dialect of English. It is demonstrably false. Furthermore, there is an actual Okinawan dialect of Japanese, which borrows elements from the Okinawan language and infuses it with Japanese. So, where did the Ryukyuan languages come from? This is a question that goes hand in hand with theories about where Ryukyuan people come from. George Kerr, author of Okinawan: The History of an Island People (An old book, but necessary read if you’re interested in Okinawa), theorised that Ryukyuans and Japanese split from the same population, with one group going east to Japan from Korea, whilst the other traveled south to the Ryukyu Islands. “In the language of the Okinawan country people today the north is referred to as nishi, which Iha Fuyu (An Okinawn scholar) derives from inishi (’the past’ or ‘behind’), whereas the Japanese speak of the west as nishi. Iha suggests that in both instances there is preserved an immemorial sense of the direction from which migration took place into the sea islands.” (For those curious, the Okinawan word for ‘west’ is いり [iri]). But, it must be stated that there are multiple theories as to where Ryukyuan and Japanese people came from, some say South-East Asia, some say North Asia, via Korea, some say that it is a mixture of the two. However, this post is solely about language, and whilst the relation between nishi in both languages is intriguing, it is hardly conclusive. With that said, the notion that Proto-Japonic was spoken by migrants from southern Korea is somewhat supported by a number of toponyms that may be of Gaya origin (Or of earlier, unattested origins). However, it also must be said, that such links were used to justify Japanese imperialism in Korea. Yeah, when it comes to Japan and Korea, and their origins, it’s a minefield. What we do know is that a Proto-Japonic language was spoken around Kyūshū, and that it gradually spread throughout Japan and the Ryukyu Islands. The question of when this happened is debatable. Some scholars say between the 2nd and 6th century, others say between the 8th and 9th centuries. The crucial issue here, is the period in which proto-Ryukyuan separated from mainland Japanese. “The crucial issue here is that the period during which the proto-Ryukyuan separated(in terms of historical linguistics) from other Japonic languages do not necessarily coincide with the period during which the proto-Ryukyuan speakers actually settled on the Ryūkyū Islands.That is, it is possible that the proto-Ryukyuan was spoken on south Kyūshū for some time and the proto-Ryukyuan speakers then moved southward to arrive eventually in the Ryūkyū Islands.” This is a theory supported by Iha Fuyu who claimed that the first settlers on Amami were fishermen from Kyūshū. This opens up two possibilities, the first is that ‘Proto-Ryukyuan’ split from ‘Proto-Japonic’, the other is that it split from ‘Old-Japanese’. As we’ll see further, Okinawan actually shares many features with Old Japanese, although these features may have existed before Old-Japanese was spoken. So, what does Okinawan look like? Well, to speakers of Japanese it is recognisable in a few ways. The sentence structure is essentially the same, with a focus on particles, pitch accent, and a subject-object-verb word order. Like Old Japanese, there is a distinction between the terminal form ( 終止形 ) and the attributive form ( 連体形 ). Okinawan also maintains the nominative function of nu ぬ (Japanese: no の). It also retains the sounds ‘wi’ ‘we’ and ‘wo’, which don’t exist in Japanese anymore. Other sounds that don’t exist in Japanese include ‘fa’ ‘fe’ ‘fi’ ‘tu’ and ‘ti’. Some very basic words include: はいさい (Hello, still used in Okinawan Japanese) にふぇーでーびる (Thank you) うちなー (Okinawa) 沖縄口 (Uchinaa-guchi is the word for Okinawan) めんそーれー (Welcome) やまとぅ (Japan, a cognate of やまと, the poetic name for ‘Japan’) Lots of Okinawan can be translated into Japanese word for word. For example, a simple sentence, “Let’s go by bus” バスで行こう (I know, I’m being a little informal haha!) バスっし行ちゃびら (Basu sshi ichabira). As you can see, both sentences are structured the same way. Both have the same loanword for ‘bus’, and both have a particle used to indicate the means by which something is achieved, ‘で’ in Japanese, is ‘っし’ in Okinawan. Another example sentence, “My Japanese isn’t as good as his” 彼より日本語が上手ではない (Kare yori nihon-go ga jouzu dewanai). 彼やか大和口ぬ上手やあらん (Ari yaka yamatu-guchi nu jooji yaaran). Again, they are structured the same way (One important thing to remember about Okinawan romanisation is that long vowels are represented with ‘oo’ ‘aa’ etc. ‘oo’ is pronounced the same as ‘ou’). Of course, this doesn’t work all of the time, if you want to say, “I wrote the letter in Okinawan” 沖縄語で手紙を書いた (Okinawa-go de tegami wo kaita). 沖縄口さーに手紙書ちゃん (Uchinaa-guchi saani tigami kachan). For one, さーに is an alternate version of っし, but, that isn’t the only thing. Okinawan doesn’t have a direct object particle (を in Japanese). In older literary works it was ゆ, but it no longer used in casual speech. Introducing yourself in Okinawan is interesting for a few reasons as well. Let’s say you were introducing yourself to a group. In Japanese you’d say みんなさこんにちは私はフィリクスです (Minna-san konnichiwa watashi ha Felixdesu) ぐすよー我んねーフィリクスでぃいちょいびーん (Gusuyoo wan’nee Felix di ichoibiin). Okinawan has a single word for saying ‘hello’ to a group. It also showcases the topic marker for names and other proper nouns. In Japanese there is only 1, は but Okinawan has 5! や, あー, えー, おー, のー! So, how do you know which to use? Well, there is a rule, typically the particle fuses with short vowels, a → aa, i → ee, u → oo, e → ee, o → oo, n → noo. Of course, the Okinawan pronoun 我ん, is a terrible example, because it is irregular, becoming 我んねー instead of  我んのー or 我んや. Yes. Like Japanese, there are numerous irregularities to pull your hair out over! I hope that this has been interesting for those who have bothered to go through the entire thing. It is important to discuss these languages because most Ryukyuan languages are either ‘definitely’ or ‘critically’ endangered. Mostly due to Japanese assimilation policies from the Meiji period onward, and World War 2. The people of Okinawa are a separate ethnic group, with their own culture, history, poems, songs, dances and languages. It would be a shame to lose something that helps to define a group of people like language does. I may or may not look in the Kyūshū dialects of Japanese next time. I’unno, I just find them interesting.