text:
Visual Language Interpreting/Tools of the Trade

Homicide Cartel ( 187 Cartel )

Homicide Cartel aka 187 Cartel was made in July of 2017 by OG Ocho from OriginalBlockMafiaFamily and King Capone and TG from FastMoneyKings. Ocho and King was homies and had the same mission as each other, and it was to Money Power and Respect. They decided to come up with a gang that could bring them closer to each other, Ocho came up with the name Homicide Cartel and King agreed, Homicide Cartel became the main source and FastMoneyKings and OriginalBlockMafiaFamily the sets of it.KeKe girlfriend of TG was OG of FastMoneyQueens which was connected to FastMoneyKings wanted apart of it. So OriginalBlockMafiaFamily became the 1st set of Homicide Cartel, FastMoneyKings 2nd set and FastMoneyQueens 3rd set, this was a new come up in Aug of 2017 Homicide Cartel had 5sets in all from 2 new sets called FamilyAndLoyaltyOverEverything and OffThePorch. MT who is OG of FALOE and BK60 who is OG of OTP.

American Sign Language
Contrary to popular belief, American Sign Language is not international. For the most part there is a signed language for almost all countries. As with spoken languages, these vary from country to country. They are not based on the spoken language in the country of origin. And like spoken languages, they developed in antiquity.

A signed language can also be used in other contexts, where normal speech cannot be used. Native Americans were known to use a signed pidgin to facilitate communication among tribes who used different spoken languages.

American Sign Language is the dominant sign language in the United States, Canada and parts of Mexico. American Sign Language is usually abbreviated ASL, though it has also been known as Ameslan. As with other sign languages, its grammar and syntax are separate and distinct from the spoken language(s) spoken in its area of influence. Etymologically, ASL's origins stem from a nineteenth century blending of French Sign Language (LSF) when Deaf French Sign Language instructor, Leclerc, came over to the states. Other American regional and indigenous signed language systems, such as Martha's Vineyard Sign Language (MVSL), was developed by the residents of the Massachusetts island. Since there is no written form of ASL, it is possible that there may be other undocumented influences on the language, but there is no way to tell for certain.

ASL is a natural language as proved to the satisfaction of the linguistic community and by the research findings of William Stokoe. It is a manual language meaning that the information is expressed not with combinations of sounds, but with combinations of handshapes, movements of the hands, arms and body, and facial expressions.

Manual Codes of English
Manual codes of English (MCE) are signing systems (not languages) that utilize the manual component of a signed (read: nonverbal) language to convey the grammatical and syntactical structure of spoken English. They do not share the grammatical and syntactical structure of American Sign Language. Historically, there have been several attempted MCE systems, viz:

Signed English (SE)
Signed English is a simplified English-based code, SE only added fourteen grammatical markers. SE was developed in the mid-1970s by Harry Bornstein at Gallaudet College, and further explored in 1983 by Bornstein, Saulnier, & Hamilton. (See Gustason, G. (1990). Signing exact English and Bornstein, H. (1990). Signed English. In H. Bornstein (ed.) Manual Communication: Implications for Education. Washington, D.C.: Gallaudet University Press.)

Seeing Essential English, or, formerly ‘SEE1’
Intended to reinforce basic English morphemic structure, in SEE1: SEE1 was developed in 1966 by David Anthony at Gallaudet College. SEE1 is no longer in use today.
 * 1) compound words are formed with separate signs (‘butter’+‘fly’)
 * 2) the same sign is used for homonyms (‘bear’ and ‘bare’)
 * 3) there is a heavy use of initialization (haVe)
 * 4) affixes, articles, and ‘to be’ verb were added

Signing Exact English, or, formerly ‘SEE2’
SEE2 is very similar to SEE1, however: SEE2 was developed in 1972 by Gerilee Gustason; SEE2 is currently the “signed English” that is used in American school systems. (This is the ‘Signing Exact English‘ referred to below.)
 * 1) compound words are conceptually accurate (‘butterfly,’ not ‘butter’+ ‘fly’)
 * 2) more ASL signs (one sounded word = one sign) are used
 * 3) there are at least seventy artificial/invented signs and affixes added to this system

Linguistics of Visual English (LOVE)
The LOVE system was a chirography system based on Seeing Essential English modes; it used the Stokoe Notation System (tab-dez-sig) to codify sentence structure. Unfortunately, there is very little explanation and/or examples extant of the LOVE system. LOVE was developed in 1972 by Dennis Wampler.

The Rochester Method
So-called because it was developed in 1878 by Zenas Westervelt, a teacher at the Western New York Institute for Deaf-Mutes (later Rochester School for the Deaf), in the Rochester Method, every word is fingerspelled. Sometimes used in tactile signing situations, some Deaf adults still use this method.

Signing Exact English
Signing Exact English (SEE) is a system of signing that strives to be an exact representation of English. It is an artificial system that was devised in 1972. It takes much of its vocabulary of signs from American Sign Language (ASL). However, it often modifies the handshapes used in the ASL signs in order to incorporate the handshape used for the first letter of the English word that the SEE sign is meant to represent. SEE can be thought of as a code for visually representing spoken English. It is used most often with Deaf children in educational settings - the initial goal of SEE was to facilitate the learning of English. It often finds use in the home too, however, as it is often welcomed as an alternative to ASL by hearing parents of Deaf children because it does not require them to learn a new grammar or syntax. Therfore, it is easier learn for people who have already internalized English. It is not often used by adult Deaf people except to communicate with hearing people who know some sign but who are not fluent users of ASL. SEE is not a single coded sign: there is SEE1, SEE2, L.O.V.E, MCE, and more.

As with almost every aspect of the education of deaf children, the use of SEE is mired in controversy concerning its efficacy and utility. In a way, it is a slight variation of the oralist vs. manualist controversy which has pitted those that have supported the use of sign language against those that believed in lipreading and speech therapy as the best way to educate deaf children. This debate has raged for centuries.

Cued Speech
Cued speech is a manual system which, when produced near the mouth while speaking, helps the Deaf disambiguate the phonemes in spoken language. Cued speech combines eight arbitrary handshapes and four locations to visually and phonetically approximate the sounds of English. While not a signed language, it is a visual means of representing spoken language segments. Developed in 1966 by Dr. Robert Cornett, an engineer at Gallaudet College, as an educational and communicative tool for the Deaf.

Consecutive Interpreting
In its purest form, consecutive interpretation is a mode in which the interpreter begins their interpretation of a complete message after the speaker has stopped producing the source utterance. At the time that the interpretation is rendered the interpreter is the only person in the communication environment who is producing a message. In practice, a consecutive interpretation may be rendered when the interpreter does not have a text in its entirety, that is, the person delivering the source utterance may have more to say, but the interpreter has enough information to deliver a message that could stand alone if need be. It is important to note that although the person who originated the message has ceased their delivery of new information, this speaker has not necessarily given up the floor and, once the interpretation has been delivered, the speaker may resume delivery of their message.

Though most people may be more familiar with simultaneous interpretation, where the interpreter renders their interpretation while still receiving the source utterance, consecutive interpretation has distinct advantages in certain interpreting situations, not the least of which is that consecutive interpretations render more accurate, equivalent[i], and complete target texts. In fact, the two modes, when performed successfully, employ the same cognitive processing skills, with the only difference being the amount of time that elapses between the delivery of the source utterance and the delivery of theinterpretation. This being the case, mastery of techniques used in consecutive interpretation can enhance an interpreter’s ability to work in the simultaneous mode. The Interpreting Process

Before we continue I would like to take a moment to explain the interpreting process in order to explain how consecutive interpretations produce more accurate and equivalent target texts. In order to interpret a text the interpreter must be able to receive and understand the incoming message and then express it’s meaning in the target language. In order to accomplish this task, the interpreter must go through an overlapping series of cognitive processing activities. These include: attending to the message, concentrating on the task at hand, remembering the message, comprehending the meaning of the message, analyzing the message for meaning, visualizing the message nonverbally, and finally reformulating the message in the target language[ii]. Seleskovitch (1978) compresses these tasks into three steps, noting that the second step includes the, “Immediate and deliberate discarding of the wording and retention of the mental representation of the message” (Seleskovitch, 8); interpreters often refer to this as “dropping form.”  By discarding the form (words, structure etc.) of the source text the interpreter is free to concentrate on extracting and analyzing the meaning of the text, and conceiving strategies for reformulating the message into the target language.

Seleskovitch, among others, points out that there is another practical reason for the interpreter to discard the form of the source text, there is only so much that a person can hold in their short-term memory. As the interpreter receives the source text the information passes initially through their short-term memory. If the interpreter does not do anything with this information it will soon disappear. Smith (1985) notes that, “Short term memory...has a very limited duration. We can remember...six or seven items only as long as we give all of our attention to them” (Smith, 38). If an interpreter attempts to retain the form of a source utterance their short-term memory will be quickly filled with individual lexical items, which may not even compose a full sentence. If the interpreter then attempts to find a corresponding lexical item in the target language for each of the source language forms in their short-term memory all of their attention will be wasted on translating these six items rather than attending to the incoming message, as Smith points out, “as long as pay attention to short-term memory we cannot attend to anything else” (Smith, 38). In a consecutively interpreted situation this would result in the interpreter stopping the speaker every six or seven words so that the interpreter could clear their short-term memory and prepare to receive new information. Cleary this is not a preferable manner in which to communicate, and, as Seleskovitch points out, it would require the interpreter to know every existing word in both languages.

It is because of the limitations of short-term memory that interpreters are required to drop form and concentrate on meaning. Both Seleskovitch and Smith propose that meaningful segments of great size can be placed into long-term memory and retrieved later. Of course a chunk of information must be understood in order to be meaningful. To demonstrate this idea Seleskovitch uses the example of a person who has just seen a movie, after viewing the film the person will be able to relate the plot and many of the details of the film. If the person continues to discuss the film with others the details will remain fresh in their mind for a longer period of time. In this example the person is able to remember the film because they understood it, and are, “conversant with the various themes found in films...the movie-goer can easily and fully process the ‘information’ conveyed...and for this reason he remembers” (Seleskovitch, 1979, 32). Smith adds, “it takes no longer to put a rich and relevant chunk of meaning into long-term memory than it does a useless letter or word” (Smith, 45), because of this the moviegoer will probably be able to relate the salient points of the film in a fraction of the time it took them to receive the information. Since the information was understood, its salient points can be reformulated into another mode of communication. For example, when the moviegoer discusses the plot of the film they do not recreate its form, nor do they take two hours to render their “interpretation.”

Due to the greater ease of assimilating larger meaningful chunks of information it behooves the interpreter to focus their attention on these larger chunks. A larger chunk of text will usually contain a greater amount of meaning. It is this relationship that aids the interpreter’s understanding of the source text when working consecutively. As shown above, once a chunk of information is understood it can be reformulated into another form. As Seleskovitch (1978) points out, “In consecutive interpretation the interpreter has the advantage of knowing line of the argument before he interprets” (Seleskovitch, 28).

Interpreters are not charged with merely understanding the message, they must also be able to remember it, in order to deliver their interpretation. Seleskovitch notes that dropping form aids the interpreter’s memory because they are not concentrating on remembering the words, or even the structure of the source text. Instead, the interpreter understands the message, connects it to long-term memory, and is then able to reformulate it in much the same way the moviegoer can relate the points of a film. Of course the interpreter must provide a more equivalent target text than the moviegoer. To this end interpreters working consecutively will often make notes as they take in the source utterance. These notes help the interpreter retrieve the message from their long-term memory and consist of, “symbols, arrows, and a key word here or there” (Seleskovitch, 1991, 7). These few notes are effective because interpreters do not produce their target texts based on the form used by the speaker but on what they understood of the meaning of the source text. The “key words” may consist of words that will remind the interpreter of the speaker’s point, or of specific information “such as proper names, headings and certain numbers” (Seleskovitch, 1978, 36).

Seleskovitch also points to the time afforded an interpreter working in the consecutive mode as an asset in reformulating the message in the target language. Because the interpreter does not need to split their attention between receiving the message, and monitoring their output, as is required in simultaneous, they can devote more of their processing to analysis and reformulation of the text thereby producing a more accurate and equivalent interpretation.

Situations for Consecutive Interpreting

Even though the interpreter’s goal is always to produce the most accurate and equivalent target text possible consecutive interpretation is not always possible. Situations where one speaker maintains the floor, with little or no interaction with the audience and situations where there is rapid turn taking between a group of interlocutors may require the interpreter to work simultaneously. While Seleskovitch notes that spoken language interpreters working at international conferences may sometimes interpret entire speeches consecutively, the consecutive mode often requires some type of pause so that the interpreter may render the message.

That said, there are situations that lend themselves to consecutive interpretation, I would like to discuss three such situations, one general, and two specific. In general, consecutive interpretation can be employed successfully in one-on-one interpreted interactions. One-on-one interactions often allow for more structured turn taking behavior than large group situations. Interviews, parent teacher meetings, and various type of individual consultations may be interpreted consecutively with minimal disruption to the flow of communication perceived by the participants.

Specifically, there are two types of interpreted situations that, due to the consequences involved, require consecutive interpretation rather than simultaneous. These are legal and medical interpreted interactions. In these situations, where a person’s life or freedom is at stake, accuracy and equivalence are of the utmost priority; as we have seen, consecutive interpretation provides greater accuracy and equivalence than simultaneous does. Palma (1995) points out that the density and complexity of witness testimony requires the interpreter to work consecutively, and to be aware of how long a chunk they can manage effectively. Palma notes that, especially during expert witness testimony, where the language used can be highly technical and is more likely to use complex sentence constructions; a segment of text that is short in duration may be extremely dense in terms of the content and complexity of its ideas. In this case the consecutive mode has the added advantage of allowing the interpreter to ask speaker to pause so that the interpreter may deliver the message. The interpreter may also take advantage of the time in which they hold the floor to ask the speaker for clarification. Use of the consecutive mode is also helped by the fact that court officials (attorneys, judges etc.) may be familiar with the norms of consecutive interpretation and by the fact that turn taking between the witness and the attorney often proceeds with only one the two speaking at any one time.

In the case of medical interpreting accuracy and equivalence are also at a premium due to the possible consequences of a misdiagnosis. Like expert witness testimony, doctor-patient interactions may be filled with medical jargon or explanations of bodily systems that may be particularly dense for the interpreter. Again turn taking may be more structured in a one-on-one medical environment especially if the patient is in full control of theirfaculties. As in the legal setting, the medical interpreter may take advantage of the structure of a doctor-patient interaction in order to request for pauses and clarifications.

Generally, the logistics of a consecutively interpreted interaction must be established before the communication takes place. In the case of a single speaker who will have little or no interaction with the audience this means either the speaker will pause for the interpreter, or the interpreter, and hopefully the audience, knows that the interpretation will not be delivered until the speaker has finished. Establishing the logistics with all the parties involved, before the interpreted interaction takes place, can help prevent the uneasiness that participants often feel while waiting for the interpreter to begin.

Consecutive in Relation to Simultaneous

As mentioned above the primary difference between consecutive and simultaneous interpreting is involves the time lapse between the delivery of the speaker’s message and the beginning of the interpretation. While this is a significant difference, one that provides more challenges for the interpreter, at their roots consecutive and simultaneous interpreting modes stem from the same set of cognitive processes. These processes are described by many interpreting theorists, (Gish, 1986-1994; Colonomos, 1989; Isham, 1986), while Seleskovitch (1978) establishes the parallel between consecutive and simultaneous. According to Seleskovitch an interpreter working in the simultaneous mode uses the same strategies, dropping form, analyzing the message for meaning, and developing a linguistically equivalent reformulation, as does the interpreter working consecutively. After all, the goal is the same for both interpreters; to deliver an accurate and equivalent target text. The difference is that in the simultaneous mode the interpreter continues to receive and process new information while rendering, and monitoring the target for equivalence. Because interpreters working in the simultaneous mode are still interpreting meaning rather than form they also allow for a lag between themselves and the speaker. That is, the interpreter waits until the speaker has begun to develop their point before beginning to interpret. By allowing for lag time, and the interpreter ensures that they are interpreting meaning, not just individual lexical items, which Seleskovitch suggests would be an exercise in futility.

“Even memorizing a half dozen words would distract the interpreter, whose attention is already divided between listening to his own words, and those of the speaker...His memory does not store the words of the sentence delivered by the speaker, but only the meaning those words convey.” (Seleskovitch, 1978, 30-31)

Seleskovitch solidifies the correlation between the cognitive processes involved in each mode when she states, “simultaneous interpretation can be learned quite rapidly, assuming one has already learned the art of analysis in consecutive interpretation” (Seleskovitch, 30). This view has been adopted at interpreter training programs at both California State University Northridge and Gallaudet University, both of whom require classes teaching text analysis and consecutive interpreting skills prior to those dealing with simultaneous interpreting.

Conclusion

Rather than being two separate skills, mastery of consecutive interpretation is in fact a building block for successful simultaneous interpretations. In fact, thanks to the time allowed for comprehension and analysis of the source text consecutive interpretations offer greater accuracy and equivalence than do simultaneous interpretations. There are situations that lend themselves to consecutive interpretations (one-on-one interactions), and others still which require use of the consecutive mode (legal, medical) due to the consequences of a possible misinterpretation.

[i]           For the purposes of this chapter, “accuracy” relates to the content of the text, while “equivalence” relates to the ability of the target text to convey the register, affect, and style of the source text. An “accurate” interpretation will provide the target language audience with all of the information contained in the source text, while an equivalent interpretation will provide the content, and also have the same effect on the target language audience as it would on a source language audience. By there definitions an interpretation may be accurate, without being totally equivalent, while an equivalent interpretation assumes accuracy.

[ii] List of cognitive processing skills taken from class notes in Risa Shaw’s Gallaudet University class “ITP 724, Cognitive Processing Skills; English” (2002)


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Talk:Electronics/Aim

Dear people editing this book, while math is useful and does have its place in an electronics textbook, it makes it very hard for people to understand electronics. So I ask the people editing this book to somehow make a clear division between theory and practice. Ideally I would like people with no background in electronics or math to be able to understand electronics. By a similar token, I'm sure that everyone editing this book would appreciate a rigorous explaination of electronics. The main reason I say this is that electronics is one of the most misunderstood subjects in existence, and unlike gravity very few people have any sort of intuition about E&M.

In reading A Brief History of Time by Steven Hawking he said (and I paraphrase) that his editor told him that for each formula that he included in his book the readership would drop by one half. As a result the only formula he included was the one Einstein is famous for. I would suggest you keep that in mind as you add math equations. Decide if the equation you are adding really adds enough value to the work to justify the loss of half the readers being able to comprehend the passage. Not saying to leave them out, but don't add them for their own sake.

The aim of this textbook is to educate someone with little or no previous experience in electronics to a 1 or 2 year level. This includes a thorough understanding of DC and AC electronics concepts, and an introduction into logic gates and digital electronics, which should be covered in another textbook.

''I think we need to establish what they do know, so we know how in depth we should go. What is our target audience?''

I think we should go as far as we can adequately explain. Meaning we can include anything we want but we have to be rigorous about the theory. If this means giving a summary of specific results from other fields, then so be it. The idea is not to prove everything in that field, but to tell how it relates to electronics. A good balance would be to focus on the theory and to provide a link to the math. That way we can cater to everyone, both newbies and the people who understand electronics.

My idea for the road map for this book:
 * Electricity
 * Charge
 * Voltage
 * Current
 * Resistance
 * Ideal circuits & real circuits (and a description of the difference between schematics that just show wiring between real components, and schematics which show the ideal functioning of components)
 * Ideal voltage and current sources
 * Ideal nodes and meshes
 * Capacitors
 * Inductors
 * Introduce magnetism here or in the electricity section?
 * Transformers
 * Controlled voltage and current sources
 * Other types of components
 * Diodes
 * Bridge rectifiers, LEDs, etc.
 * Transistors (presenting these as controlled variable resistors is more intuitive than as "amplifiers" or controlled voltage sources)
 * BJTs
 * FETs
 * Vacuum tubes
 * Op-amps next?
 * Digital circuits
 * AND OR gates
 * other gates
 * Show how every gate can be built with a NAND or whatever
 * Radio can come after all of that

''Your road map looks similar to what we have except minus the section on power. Also I am not sure how big a difference there is between ideal and real. What major structural changes you would like to make to the book?''

 * I just meant I think it should be in this order.

=Difference between ideal and real circuits=

A real circuit diagram shows real components and how they are connected:

An ideal circuit diagram shows how each components functions, using ideal components (perfect voltage sources, perfect resistors, etc.) This is what allows us to do mathematical calculations to determine how the circuit works:

The circuit can be even more idealized by showing things that wouldn't have an effect normally, but might in specific situations. Every resistor has some capacitance and inductance, every capacitor has some resistance and inductance, every opamp has some input current, input capacitance, output resistance, finite gain, parasitic capacitances, etc etc etc). All of these would have a huge effect on circuit performance if the circuit is operating near MHz frequencies, for instance.

Now I am thinking we should just have an explanation of the difference between the two types of circuit diagrams first. Then when we introduce each component, we will tell how it ideally behaves, and how a real component behaves. All coils have non-negligible resistance, for example, and all diodes have at least a little voltage drop.

/ I understand that you feel this is an important topic, but try not to go overboard in covering it, for all practical purposes, ideal circuits can be used without much problem.

Electronics vs. Practical Electronics
May I propose that this textbook be concerned with how the components works, and the textbook Practical Electronics be concerned with how to make circuits work, along with tips and tricks like good soldering technique, etc? That way, people who just want to learn how to do something without trawling through the equations can do it at Practical Electronics, and those who would like to know exactly why somethings works can do so here. Otherwise, both sides lose out.

Just a thought, as it seems to me that PE is otherwise just another version of this book

Also, I thnk that perhaps this books should just have a basic overview of semiconductors, and PE can take care of the practicalities (which transistor to use for what, etc), and Semiconductors can take care of the equations and physics. Otherwise, this book stands to have a huge chunk of information that exists in common with Semiconductors .

Inductiveload 23:44, 7 September 2006 (UTC)

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Talk:Electronics/Aim


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Cookbook:Curried Rice

| Vegetarian Cuisine

Ingredients

 * 1 cup (125 g/4.4 oz) uncooked brown rice or white rice
 * 2 tablespoons butter
 * 1 teaspoon curry powder
 * ½ onion, chopped
 * ½ cup (60 g) raisins
 * 2 cups (500 ml/1.1 pint) water
 * 3 vegetarian or chicken bouillon cubes

Procedure

 * 1) Find a large saucepan or frying pan which has a lid, and place over medium heat.
 * 2) Add butter then chopped onion to pan. Cook the onion for a couple of minutes until it starts to brown slightly.
 * 3) Add curry powder, and stir for a minute.
 * 4) Mix in vegetarian bouillon cubes, raisins, rice, and water.
 * 5) Put on pan lid and simmer until water is absorbed (about 15 minutes).

simple:Cookbook:Curried Rice

title: Cookbook:Curried Rice


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Cookbook:French Toast

| Vegetarian | Breakfast

French toast is a common breakfast or dessert item made by frying a piece of bread soaked in an egg batter. French toast was developed as a way to use day-old stale bread. The literal translation of pain perdu is lost bread, referring to old or stale bread. When lacking stale bread, toasting your bread lightly will help it absorb more of the egg and milk batter.

French toast is usually served with toppings similar to those used for pancakes, waffles, and toast. It can also be served as part of a fried breakfast with savory foods like sausages, tomato (or ketchup), baked beans, fried mushrooms etc.

This recipe is easily scalable.

French toast

 * 1 egg
 * About ¼ cup (60 ml / 2 oz) milk or cream (more for softer, less eggy French toast; less for firmer, more eggy toast)
 * 2–3 slices bread (see notes)
 * Butter, margarine, or cooking oil

Optional flavorings

 * ½ teaspoon vanilla extract or similar
 * ¼–1 teaspoon nutmeg, cinnamon or other powdered spices suitable for sweet foods
 * ½ teaspoon sugar or honey
 * ¼ teaspoon salt
 * ¼ teaspoon pepper

Suggested toppings

 * Maple syrup
 * Jam, jelly, fruit syrup
 * Whipped cream
 * Powdered sugar
 * Nuts
 * Honey
 * Bacon
 * Raspberries, strawberries, blueberries, and/or bananas

Procedure

 * 1) In a bowl, mix eggs and milk, and optional ingredients.
 * 2) Heat up a frying pan, skillet, or griddle to medium-low heat.
 * 3) Grease the pan with butter, margarine, or cooking spray.
 * 4) Soak a slice of bread in the egg-milk mixture and place on pan; repeat until pan is full or desired amount is placed.
 * 5) Cook, turning once, until both sides of the bread are browned and the inside is cooked through.
 * 6) Serve on plates, with toppings as desired.

Notes, tips, and variations

 * The goal is to get both sides of the French toast nicely browned, while making sure the center is cooked. Using excessive heat could scorch the outside of the toast while leaving the inside undercooked.

 * If making a small batch, soak the two slices until almost all of the mixture has been absorbed. If the bowl is small, place the two slices on top of each other, and keep switching and flipping them, so that all four sides will absorb the mixture.

 * The cooking process is too short to use most raw spices, but some fresh herbs might be very tasty.

 * If using sandwich bread, a plastic sandwich container may be used for the egg-milk mixture. This allows maximum use of the mixture, as the container is a good size and shape.

 * Toast your bread before dipping it into the mix to create a solid base.
 * The following types of bread are good used for French toast. Hard crust breads are recommended. Softer breads will create a soggy toast.
 * Sourdough
 * Challah
 * Schiacciata
 * Portuguese sweet bread ("Massa Suvada"). This bread will take your french toast to new heights.
 * Whole-wheat raisin bread or schiacciata.
 * King's Hawaiian Sweet Bread
 * Panettone (bread with raisin, but may be too sweet for some)
 * Brioche (weaved bread)
 * Chinese bakery loaves of bread. Ask to get it cut thick or uncut.

프렌치 토스트

title: Cookbook:French Toast


text:
User talk:Klaus

Gentgeen, A belated thanks for the welcome. =) Chris Klaus 10:59, 22 May 2006 (CST)

Klaus, Welcome to Wikibooks! I see you've been adding recipes to the Cookbook, and I wanted to thank you. If you have any questions, ask me on my talk page or ask at the Staff lounge. Gentgeen 03:44, 3 May 2004 (UTC)

title: User talk:Klaus


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Cookbook:Vegetarian Soft Tacos

| Southwestern Cuisine

Ingredients

 * 2 tablespoons chilli powder
 * 1½ tablespoons paprika
 * 1 cup diced onions
 * ½ tablespoon salt
 * 2 cloves minced garlic
 * 1 dash red pepper
 * 1 pound ground beef substitute (e.g. MorningStar Farms Grillers Recipe Crumbles)
 * 1 cup water
 * 8 flour tortillas

Suggested toppings

 * 1 can refried beans
 * 1 tomato, chopped
 * 1 cup chopped onion
 * 2 cups shredded lettuce
 * 1 cup shredded Colby-Jack cheese (or cheddar)
 * sour cream

Procedure

 * 1) In a frying pan brown onions on medium-low heat.
 * 2) Add garlic, chilli powder, paprika, salt, and red pepper. Stir and cook for 1 minute.
 * 3) Add beef substitute and water. Cook for 10–15 minutes until most of the water is gone.
 * 4) Meanwhile chop and shred the toppings as needed. Put toppings in bowls on table.
 * 5) Start to warm refried beans in a small pot.
 * 6) Heat another frying pan on medium-low heat.
 * 7) Put vegetarian taco meat and refried beans in bowls and place on table.
 * 8) Put floured tortilla in pan and lightly brown both sides. As tortillas are ready allow guests to select their own toppings.

Notes, tips, and variations

 * The filling and refried beans keep well in the refrigerator.

title: Cookbook:Vegetarian Soft Tacos


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Cookbook:Leavening Agent

| Basic foodstuffs

Leavening agents are used to make bread and other foods rise, trapping many little air bubbles in the food. This gives the final product a less dense, lighter consistency than it would have if leavening had not taken place. The various methods for leavening include biological and chemical reactions, as well as mechanically trapping air in a substance.

Chemical leavening
These leavening agents work by releasing carbon dioxide gas as they react with water, heat, or acid in the food.

 * baking powder
 * baking soda (sodium bicarbonate)
 * horn salt (hartshorn - ammonium bicarbonate)

Biological leavening
These leavening agents work by fermenting sugars in the food to produce carbon dioxide. The fermentation typically produces additional flavour compounds, such as the sour flavours in sourdough bread.

 * beer (unpasteurised - live yeast)
 * buttermilk
 * ginger beer
 * kefir
 * sourdough starter
 * yeast
 * yoghurt

Mechanical leavening
These leavening agents work either by releasing gas already trapped in the product, or by incorporating air into the product by beating / stirring. If a gas is used, it is usually carbon dioxide, although sometimes nitrous oxide is used (as in the case of canned whipped cream).

 * beer (pasteurised - no live yeast)
 * egg whites (whipped)
 * whipped cream

title: Cookbook:Leavening Agent


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Electronics/Crystals

< ../Expanded Edition/

The vast majority of crystals used in electronics are piezoelectric crystals.

The piezoelectric effect (converting back and forth between electrical voltage and mechanical position) makes quartz crystals physically vibrate. The quartz crystal can be cut into the right shape and appropriately mounted so that it "rings" (vibrates) only at one precise frequency, useful for clock circuits.

Some quartz crystals are used as SAW filters.

PZT crystals are used in ultrasonic devices such as Medical ultrasonography. They use the piezoelectric effect to convert electrical energy to sound energy to send out a pulse, then convert the sound energy of the echo back to electrical energy.

other
(The atomic clocks in GPS satellites use the oscillations of cesium atoms in gas form as the time reference. That gives far better precision than any known crystal oscillator.)

title: Electronics/Crystals


text:
Geometry/Area

Area of Circles
The method for finding the area of a circle is
 * $$Area=\pi r^2$$

Where $$r$$ is the radius of the circle; a line drawn from any point on the circle to its center.

Area of triangles
Three ways of calculating the area inside of a ../Triangle/ are mentioned here.

First method
If one of the sides of the triangle is chosen as a base, then a height for the triangle and that particular base can be defined. The height is a line segment perpendicular to the base or the line formed by extending the base and the endpoints of the height are the corner point not on the base and a point on the base or line extending the base. Let B = the length of the side chosen as the base. Let h = the distance between the endpoints of the height segment which is perpendicular to the base. Then the area of the triangle is given by:
 * $$Area=\frac{B\cdot h}{2}$$

This method of calculating the area is good if the value of a base and its corresponding height in the triangle is easily determined. This is particularly true if the triangle is a right triangle, and the lengths of the two sides sharing the $$90^\circ$$ angle can be determined.

Second method
, also known as Heron's Formula

If the lengths of all three sides of a triangle are known, Hero's formula may be used to calculate the area of the triangle. First, the semiperimeter, s, must be calculated by dividing the sum of the lengths of all three sides by 2. For a triangle having side lengths $$a,b,c$$ :
 * $$s=\frac{a+b+c}{2}$$

Then the triangle's area is given by:
 * $$Area=\sqrt{s(s-a)(s-b)(s-c)}$$

If the triangle is needle shaped, that is, one of the sides is very much shorter than the other two then it can be difficult to compute the area because the precision needed is greater than that available in the calculator or computer that is used. In otherwords Heron's formula is numerically unstable. Another formula that is much more stable is:
 * $$Area=\frac{\sqrt{\big(a+(b+c)\big)\big(c-(a-b)\big)\big(c+(a-b)\big)\big(a+(b-c)\big)}}{4}$$

where $$a,b,c$$ have been sorted so that $$a\ge b\ge c$$.

See also Heron's Formula at MathWorld and How JAVA's Floating-Point Hurts Everyone Everywhere

Third method
In a triangle with sides length $$a,b,c$$ and angles $$\alpha,\beta,\gamma$$ opposite them,
 * $$A=\frac{ab\sin(\gamma)}{2}=\frac{bc\sin(\alpha)}{2}=\frac{ac\sin(\beta)}{2}$$

This formula is true because $$h=\sin(\gamma)$$ in the formula $$A=\frac{Bh}{2}$$. It is useful because you don't need to find the height from an angle in a separate step, and is also used to prove the law of sines (divide all terms in the above equation by $$a\cdot b\cdot c$$ and you'll get it directly!)

Area of rectangles
The area calculation of a rectangle is simple and easy to understand. One of the sides is chosen as the base, with a length $$b$$. An adjacent side is then the height, with a length $$h$$, because in a rectangle the adjacent sides are perpendicular to the side chosen as the base. The rectangle's area is given by:
 * $$A=b\cdot h$$

Sometimes, the baselength may be referred to as the length of the rectangle, l, and the height as the width of the rectangle, w. Then the area formula becomes:
 * $$A=l\cdot w$$

Regardless of the labels used for the sides, it is apparent that the two formulas are equivalent.

Of course, the area of a square with sides having length $$s$$ would be:
 * $$A=s^2$$

Area of parallelograms
../Parallelograms/ are described in their own chapter.

The area of a parallelogram can be determined using the equation for the area of a rectangle. The formula is:
 * $$A=b\cdot h$$

The height is a perpendicular line segment that connects one of the vertices to its opposite side (the base).
 * $$A$$ is the area of a parallelogram.
 * $$b$$ is the base.
 * $$h$$ is the height.

Area of a rhombus
Remember in a rombus all sides are equal in length.
 * $$A=\frac{d_1\cdot d_2}{2}$$

where $$d_1,d_2$$ represent the diagonals.

Area of trapezoids
The area of a trapezoid is derived from taking the arithmetic mean of its two parallel sides to form a rectangle of equal area. $$A=\frac{(b_1+b_2)\cdot h}{2}$$ Where $$b_1,b_2$$ are the lengths of the two parallel bases.

Area of kites

The area of a kite is based on splitting the kite into four pieces by halving it along each diagonal and using these pieces to form a rectangle of equal area.
 * $$A=\frac{ab}{2}$$

Where $$a,b$$ are the diagonals of the kite.

Alternatively, the kite may be divided into two halves, each of which is a triangle, by the longer of its diagonals, $$a$$. The area of each triangle is thus
 * $$\frac{a\cdot\dfrac{b}{2}}{2}$$

Where $$b$$ is the other (shorter) diagonal of the kite.

And the total area of the kite (which is composed of two identical such triangles) is
 * $$2\cdot\frac{a\cdot\dfrac{b}{2}}{2} = a\cdot\frac{b}{2} = \frac{ab}{2} .$$

For more details see Kite (geometry).

Areas of other quadrilaterals
The areas of other ../Quadrilaterals/ are slightly more complex to calculate, but can still be found if the quadrilateral is well-defined. For example, a quadrilateral can be divided into two triangles, or some combination of triangles and rectangles. The areas of the constituent polygons can be found and added up with arithmetic.

Areas defining angles
The area of a circular sector is a fraction of the area of the whole circle. When the circle has radius that is the square root of two, the circle has area 2 π, and the radian measure of the sector corresponds to the fraction of the total circular area. In calculus, another type of angle called hyperbolic is related to the exponential function. This type of angle also corresponds to the area of a sector of the hyperbola xy=1. Use of area measure provides a means to unify these angle types. See Unified Angles.

title: Geometry/Area


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Geometry/Right Triangles and Pythagorean Theorem

Right triangles
Right triangles are triangles in which one of the interior angles is 90o. A 90o angle is called a right angle. Right triangles have special properties which make it easier to conceptualize and calculate their parameters in many cases.

The side opposite of the right angle is called the hypotenuse. The sides adjacent to the right angle are the legs. When using the Pythagorean Theorem, the hypotenuse or its length is often labeled with a lower case c. The legs (or their lengths) are often labeled a and b.

Either of the legs can be considered a base and the other leg would be considered the height (or altitude), because the right angle automatically makes them perpendicular. If the lengths of both the legs are known, then by setting one of these sides as the base ( b ) and the other as the height ( h ), the area of the right triangle is very easy to calculate using this formula:

$$Area = \,$$(1/2)$$ b h \, $$

This is intuitively logical because another congruent right triangle can be placed against it so that the hypotenuses are the same line segment, forming a rectangle with sides having length b and width h. The area of the rectangle is b × h, so either one of the congruent right triangles forming it has an area equal to half of that rectangle.

Right triangles can be neither equilateral, acute, nor obtuse triangles. Isosceles right triangles have two 45° angles as well as the 90° angle. All isosceles right triangles are similar since corresponding angles in isosceles right triangles are equal. If another triangle can be divided into two right triangles (see ../Triangle/), then the area of the triangle may be able to be determined from the sum of the two constituent right triangles. Also the Pythagorean theorem can be used for non right triangles. a2+b2=c2-2c

Pythagorean Theorem
For history regarding the Pythagorean Theorem, see Pythagorean theorem. The Pythagorean Theorem states that:

 * In a right triangle, the square of the length of the hypotenuse is equal to the sum of the squares of the lengths of the other two sides.

Let's take a right triangle as shown here and set c equal to the length of the hypotenuse and set a and b each equal to the lengths of the other two sides. Then the Pythagorean Theorem can be stated as this equation:

$$ \quad c^2 = a^2 + b^2 $$

Using the Pythagorean Theorem, if the lengths of any two of the sides of a right triangle are known and it is known which side is the hypotenuse, then the length of the third side can be determined from the formula.

Sine, Cosine, and Tangent for Right Triangles
Sine, Cosine, and Tangent are all functions of an angle, which are useful in right triangle calculations. For an angle designated as θ, the sine function is abbreviated as sin θ, the cosine function is abbreviated as cos θ, and the tangent function is abbreviated as tan θ. For any angle θ, sin θ, cos θ, and tan θ are each single determined values and if θ is a known value, sin θ, cos θ, and tan θ can be looked up in a table or found with a calculator. There is a table listing these function values at the end of this section. For an angle between listed values, the sine, cosine, or tangent of that angle can be estimated from the values in the table. Conversely, if a number is known to be the sine, cosine, or tangent of an angle, then such tables could be used in reverse to find (or estimate) the value of a corresponding angle.

These three functions are related to right triangles in the following ways:

In a right triangle,

 * the sine of a non-right angle equals the length of the leg opposite that angle divided by the length of the hypotenuse.

 * the cosine of a non-right angle equals the length of the leg adjacent to it divided by the length of the hypotenuse.

 * the tangent of a non-right angle equals the length of the leg opposite that angle divided by the length of the leg adjacent to it.

For any value of θ where cos θ ≠ 0,

$$\qquad \tan \theta = \frac {\sin \theta } {\cos \theta }$$.

If one considers the diagram representing a right triangle with the two non-right angles θ1and θ2, and the side lengths a,b,c as shown here:

For the functions of angle θ1:

$$\sin \theta_1 = \frac {b} {c} \qquad \cos \theta_1 = \frac{a} {c} \qquad \tan \theta_1 = \frac {b} {a} $$

Analogously, for the functions of angle θ2:

$$\sin \theta_2 = \frac {a} {c} \qquad \cos \theta_2 = \frac {b} {c} \qquad \tan \theta_2 = \frac {a} {b} $$

Table of sine, cosine, and tangent for angles θ from 0 to 90°
General rules for important angles: $$ sin 45^o = cos 45^o = \frac{1}{\sqrt{2}} $$

$$ tan 45^o = 1 $$

$$ sin 30^o = \frac{1}{2} = cos 60^o $$

$$ cos 30^o = \frac{\sqrt{3}}{2} = sin 60^o $$


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Using GNOME/What is GNOME

GNOME is a graphical environment designed for the GNU/Linux Operating System, but also works on other platforms (see Supported Platforms). It is designed to be usable, accessible, free (see Free Software) and internationalized. For more on GNOME see about GNOME.

The word GNOME, which is pronounced "Guh-'nome", (as it's part of the GNU Project) is an acronym for GNU Object Model Environment, and is written in all capital letters.

Contents

 * 1) History of GNOME
 * 2) Differences between GNOME and other platforms
 * 3) Supported Platforms
 * 4) Installing GNOME

Back to contents page

title: Using GNOME/What is GNOME


text:
Using GNOME/Differences

If you are new to GNOME but are used to using another desktop or an older version of GNOME, you may find GNOME's interface confusing at first. This chapter compares the terminology used between GNOME and other desktops, which will help ease the transition.

 * 1) Between GNOME and Windows
 * 2) Between GNOME and Mac OS X
 * 3) Between GNOME and CDE
 * 4) Between GNOME and KDE
 * 5) Between different distributions of GNOME
 * 6) Between older versions of GNOME

title: Using GNOME/Differences


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User:Krik

m:User:Meta-krik

title: User:Krik


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Using GNOME/File manager wastebasket

The Waste basket is a place to store unwanted files. Emptying the wastebasket deletes all files in it permanently, so make sure there is no important files in there by mistake.

You can also have the option to delete files instantly without moving it to the wastebasket first. To enable this, choose "Edit, Preferences" from the file manager window, then on the behavior tab select "Include a Delete command that bypasses Wastebasket". use this with care. It is like using a shredder to destroy a document.

Back to contents page

title: Using GNOME/File manager wastebasket


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Cookbook:Chocolate Mousse

| Cuisine of France | Dessert

Mousse au chocolat (French for "chocolate foam") is a sweet food, normally served as dessert.

Ingredients

 * 200 g (8 oz) bittersweet chocolate, chopped (see notes)
 * 3 eggs (see notes)
 * 250 ml (1 cup) cream
 * 40 g white granulated sugar
 * 30 ml (2 tablespoons) hot water

Procedure

 * 1) Melt the chocolate in a double boiler.
 * 2) Separate the eggs.
 * 3) Whip the egg whites and cream separately until very firm. Put both in the refrigerator.
 * 4) Combine the egg yolks and hot water in a mixing bowl; maximum tap water temperature is enough, approx. 50–60°C (120–140°F). Using a mixer, beat slowly while adding the sugar, then speed up the mixer until the mixture is thick and becomes a light yellow color.
 * 5) Stir the melted chocolate into the yolk mixture (the chocolate should have cooled enough that it does not hurt if you insert your finger). Mix immediately, otherwise this will cook the egg yolks, and you'll have chocolate scrambled eggs!
 * 6) With a whisk (from now on do not use the mixer) add the egg whites in three parts to the chocolate mixture, followed by the whipped cream.
 * 7) The finished mousse should be light brown and very fluffy. While it is still liquid, divide it into individual serving dishes. Allow to chill in the refrigerator for 4–6 hours before serving. The mousse will be quite firm when ready.

Notes, tips and variations

 * This recipe is not the "purest" form, which contains only bittersweet chocolate and eggs: 6 eggs for 200 g (8 oz) of chocolate; no cream, no sugar.
 * It is one of the easiest recipes for untrained cooks. The only "difficult" parts are separating the eggs and folding the egg whites.
 * For the more advanced cook: use a fourth yolk (and only the yolk!); it ensures that the mousse becomes firm. However, the mixture must be worked faster, beginning with the addition of the chocolate to the yolk/sugar mixture.
 * Instead of the water, use an alcoholic spirit such as Cognac, Cointreau, Kahlua, Triple Sec, etc., for all or part of the 30 ml. However, the mousse is then not suitable for children or pregnant women.
 * Coffee can also be satisfyingly substituted for the liquid.
 * Almond powder, almond butter, or orange rind can also be used to add flavor to the mousse (one tablespoon per 6 eggs)
 * There is also an Atkins-friendly recipe.

Warnings

 * This mousse is best consumed within 24 hours.
 * Do not keep substantially longer, even if refrigerated.

Kochbuch/ Mousse au chocolat Livre de cuisine/Mousse au chocolat Kookboek/Chocolademousse

title: Cookbook:Chocolate Mousse


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Cookbook talk:Chocolate Mousse

This recipe originally published, in German, in the Wikibooks module Kochbuch/Mousse au chocolat. Translation into English using www.worldlingo.com and freetranslation.com. Gentgeen 11:43, 3 May 2004 (UTC)

Complaint!
This seems to be almost a chocolate custard rather than a mousse. I regard mousse as simple whipped cream and chocolate (with liquid additives for desired flavour). Adding egg (although it is inarguably an excellant imulsifier) really seems to be cheating to me, not to mention making what I see as a sort of custard. #include disclaimer.h Grimm
 * I look at it differently. To me chocolate and whipped cream combine to become chocolate whipped cream, which isn't bad, but isn't mousse either.  In a mousse, the egg yolks add a richness that is lacking in chocolate whipped cream, while the whites aid the cream in making the mousse light and fluffy.  In a custard, the eggs are not seperated, which obviously means the whites aren't whipped.  Additionally, a custard is normally at least partially cooked, while a mousse remains basicly raw, other than melting the chocolate. Gentgeen 04:48, 18 Nov 2004 (UTC)
 * Hmm further reaserach shows that my origional sources are the extreme minority. Odd. Very well, move along, nothing to see here :P Grimm

Safe version?
It'd be nice to have a version that didn't involve raw eggs. I'd rather not get my family killed.

Perhaps one could get pasteurized egg whites or cheat a bit with unflavored gelatin?

brand advertisement removed
I removed "Chocolate from Lindt & Spruengli or their U.S. subsidiary Ghirardelli is highly recommended." 88.90.16.74 (talk) 21:25, 26 November 2010 (UTC)

title: Cookbook talk:Chocolate Mousse


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General Mechanics/Partial Derivatives

We will now take a break from physics, and discuss the topics of partial derivatives. Further information about this topic can be found at the Partial Differential Section in the Calculus book.

Partial Derivatives
In one dimension, the slope of a function, f(x), is described by a single number, df/dx.

In higher dimensions, the slope depends on the direction. For example, if f=x+2y, moving one unit x-ward increases f by 1 so the slope in the x direction is 1, but moving one unit y-ward increases f by 2 so the slope in the y direction is 2.

It turns out that we can describe the slope in n dimensions with just n numbers, the partial derivatives of f.

To calculate them, we differentiate with respect to one coordinate, while holding all the others constant. They are written using a ∂ rather than d. E.g.

 * $$f(x+dx,y,z)=f(x,y,z)+\frac{\partial f}{\partial x}dx \quad (1)$$

Notice this is almost the same as the definition of the ordinary derivative.

If we move a small distance in each direction, we can combine three equations like 1 to get

 * $$df= \frac{\partial f}{\partial x}dx + \frac{\partial f}{\partial y}dy + \frac{\partial f}{\partial z}dz$$

The change in f after a small displacement is the dot product of the displacement and a special vector

 * $$\left( \frac{\partial f}{\partial x}, \frac{\partial f}{\partial y}, \frac{\partial f}{\partial z} \right) \cdot \left( dx, dy, dz \right)

=\operatorname{grad} f = \nabla f $$

This vector is called the gradient of f. It points up the direction of steepest slope. We will be using this vector quite frequently.

Partial Derivatives #2
Another way to approach differentiation of multiple-variable functions can be found in Feynman Lectures on Physics vol. 2. It's like this:

The differentiation operator is defined like this: $$df = f(x + \Delta x, y + \Delta y, z + \Delta z) - f(x,y,z)\,\!$$ in the limit of $$\Delta x, \Delta y, \Delta z \to 0$$. Adding & subtracting some terms, we get

$$df = (f(x + \Delta x, y + \Delta y, z + \Delta z) - f(x, y + \Delta y, z + \Delta z)) + (f(x, y + \Delta y, z + \Delta z) - f(x, y, z + \Delta z)) + (f(x, y, z + \Delta z) - f(x,y,z))\,\!$$

and this can also be written as

 * $$df = \frac{\partial f}{\partial x}dx + \frac{\partial f}{\partial y}dy + \frac{\partial f}{\partial z}dz$$

Alternate Notations
For simplicity, we will often use various standard abbreviations, so we can write most of the formulae on one line. This can make it easier to see the important details.

We can abbreviate partial differentials with a subscript, e.g.,

 * $$D_x h(x,y)= \frac{\partial h}{\partial x}

\quad D_x D_y h= D_y D_x h$$

or

 * $$\partial_x h= \frac{\partial h}{\partial x} $$

Mostly, to make the formulae even more compact, we will put the subscript on the function itself.

 * $$D_x h= h_x \quad h_{xy}=h_{yx}$$

More Info
Refer to the Partial Differential Section in the Calculus book for more information.

title: General Mechanics/Partial Derivatives


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Template:Using GNOME

Using GNOME/Coverage | What is GNOME? | Terminology Used | Logging in | Main Desktop | Applications | Accessibility | Tips and Tricks | Power Users | Using GNOME/Further reading

title: Template:Using GNOME


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General Mechanics/Motion in Two and Three Dimensions

Motion in 2 and 3 Directions
Previously, we discussed Newtonian dynamics in one dimension. Now that we are familiar with both vectors and partial differentiation, we can extend that discussion to two or three dimensions.

Work becomes a dot product
 * $$W=\mathbf{F}\cdot \Delta x$$

and likewise power
 * $$P=\mathbf{F}\cdot \mathbf{v}$$

If the force is at right angles to the direction of motion, no work will be done.

In one dimension, we said a force was conservative if it was a function of position alone, or equivalently, the negative slope of a potential energy.

The second definition extends to
 * $$\mathbf{F}=-\nabla V$$

In two or more dimensions, these are not equivalent statements. To see this, consider

 * $$D_y\mathbf{F}_x-D_x\mathbf{F}_y=V_{xy}-V_{yx}$$

Since it doesn't matter which order derivatives are taken in, the left hand side of this equation must be zero for any force which can be written as a gradient, but for an arbitrary force, depending only on position, such as F=(y, -x, 0), the left hand side isn't zero.

Conservative forces are useful because the total work done by them depends only on the difference in potential energy at the endpoints, not on the path taken, from which the conservation of energy immediately follows.

If this is the case, the work done by an infinitesimal displacement dx must be

 * $$W=V(\mathbf{x})-V(\mathbf{x}+d\mathbf{x})=-(\nabla V)\cdot d\mathbf{x}$$

Comparing this with the first equation above, we see that if we have a potential energy then we must have

 * $$\mathbf{F}=-\nabla V$$

Any such F is a conservative force.

Circular Motion
An important example of motion in two dimensions is circular motion.

Consider a mass, m, moving in a circle, radius r.

The angular velocity, ω is the rate of change of angle with time. In time Δt the mass moves through an angle Δθ= ωΔt. The distance the mass moves is then r sin Δθ, but this is approximately rΔθ for small angles.

Thus, the distance moved in a small time Δt is rωΔt, and divided by Δt gives us the speed, v.

 * $$v = \omega r \, $$

This is the speed not the velocity because it is not a vector. The velocity is a vector, with magnitude ωr which points tangentially to the circle.

The magnitude of the velocity is constant but its direction changes so the mass is being accelerated.

By a similar argument to that above it can be shown that the magnitude of the acceleration is

 * $$a = \omega v \, $$

and that it is pointed inwards, along the radius vector. This is called centripetal acceleration.

By eliminating v or ω from these two equations we can write

 * $$\mathbf{a}= -\omega^2 \mathbf{r} = -\frac{v^2}{r}\mathbf{ \hat{ r}}

$$


text:
User:Perl~enwikibooks/Fahrenheit 451/resources

=Resources=
 * Ray Bradbury Online: A brief biography

 * Ray Bradbury biography from teenreads.com

 * Ray Bradbury's official site

 * Ray Bradbury article from Wikipedia

 * Fahrenheit 451 article from Wikipedia


text:
Guitar/Slide Guitar

Introduction
A slide is a metal/glass/ceramic tube which fits over a finger (most commonly the ring finger or little finger, but any will work). If you wish to experiment with slide guitar, but do not have a slide, objects ranging from lighters and glass bottles to sections of metal pipe and batteries can work just as well, and in some cases provide entertainment and stage presence to a performance. Do not press the string down. The slide rests on the string, not enough to give fret buzz, but enough to stop the string buzzing against the slide. Some players will lightly deaden the string behind the slide with a trailing finger to stop any unwanted vibrations.

Practice getting a crisp note without sliding first. Because the slide rests on the strings, the slide playing a single note should be directly above the fret, not behind it as with the fingers. Usually the slide guitarist keeps the slide moving backwards and forwards slightly to create a vibrato effect.

A common technique found in slide guitar is playing fingerstyle as opposed to the use of a pick or plectrum. The benefits of fingerstyle playing includes the ability to more easily pick the desired strings, while using the other fingers to dampen the other strings from undesired vibration. Raising the action of the guitar is also recommended. The normal low action, which is ideal for playing lead in standard tuning, is counter-productive when playing slide because of string buzz and lack of a clear sounding note. For this reason many guitarists have a second guitar where they raise the action to such a height to make it almost unplayable using normal technique. This high action guitar is permanently kept in an "open tuning" and is used exclusively for slide playing. Note that raising (or lowering) the action means that the intonation of the guitar has to be re-set. This can simply be done with a guitar tuner and just involves turning the string adjuster until the open string and its octave at the twelfth fret (fretted and harmonic) produce exactly the same note. Basically the needle or display of an electronic guitar tuner should settle exactly dead center regardless of whether you are playing an open high E string or fretting its octave at the twelfth fret. A guitar that is correctly set up will show this on all strings. Setting the action of electric guitars is very easy due to the string adjusters; however, acoustic guitars have their intonation set at the factory and don't have string adjusters. Adjusting the action of an acoustic should be left to a guitar shop or luthier who specializes in repair and maintenance.

Though slide guitar is often played in open chord tunings, Open G and Open D being the most common, playing slide in standard tuning is also possible and can add a new dimension to your playing. Slide guitar has always provided a fascinating approach to playing the guitar and the sound of the slide has found a home in genres such as rock and country.

History
One of the earliest mentions of slide guitar is in W.C.Handy's autobiography "Father Of The Blues":

"As he played, he pressed a knife on the strings of the guitar in a manner popularized by the Hawaiian guitarists who used steel bars"

This is also one of the earliest references to the blues. As you can tell from the quote above the use of the slide in no late-comer to the blues genre and there is large body of work from the 1920s to the present day. No guitarist can confuse the slide playing of Duane Allman with that of Robert Johnson. Each period informs of itself the dictates of taste and style.

1930s
Robert Johnson is cited as the first great slide guitarist. Other famous blues performers had comer before him, Blind "Lemon" Jefferson was a major entertainer during the 1920s but Robert Johnson is considered to be the first major exponent of the slide. During his life-time he only recorded a handful of tracks and though known locally for being a fine entertainer; the world-wide fame that is associated with his name now is more down to later blues fans and guitarists who have sought the roots of the blues.

title: Guitar/Slide Guitar


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Lucid Dreaming/Reality Checks/Powers

Presentation
With the powers reality check, you try to use "magical" powers (i.e. flying, unlocking doors without touching them, walking through objects, etc.) and see if they work; if they do, then chances are you're dreaming.

As long as you're dreaming and you expect your "magical powers" to work, then they will, and you'll hopefully realize that you must be dreaming.

Examples of this reality check working

 * I'm in a room with a locked door. I "wish" it open, and it opens. I realize I must be dreaming.
 * I'm falling off a cliff, and I try to stop falling, and start moving upwards. I start flying, and realize that I must be dreaming.

Examples of this reality check failing

 * I'm walking along a path and notice a giant green rat walking along it with me. I vaguely realize that rats are generally not 5 feet long excluding the tail, and generally don't have green fur, but I figure there must be some breed of giant rats that I've never heard of before. I decide to try levitating the rat, and doubtfully try to force the rat to start floating with my mind, but it just keeps walking. I figure that I must be awake after all, and make a note to go look up giant green rats in an encyclopaedia when I get home.
 * I'm in the guest bedroom of my grandparents' apartment. I look into the mirror above the chimney and think about transforming into a woman. However, the previous part of my dream was about me being able to transform into a woman, so I thought it was normal when I actually did, and I continued nonlucidly.
 * Sometimes when this does work, the lucidity wears off after a couple of minutes and the laws of physics kick back in. Usually this happens when I'm in midflight and it tends to get me killed in undignified ways.

Sueño lúcido/Test de Realidad/Poderes

title: Lucid Dreaming/Reality Checks/Powers


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Lucid Dreaming/Reality Checks/Memory

Presentation
With the memory reality check, you try to remember what just happened in the past few minutes, and what happened a little bit ago.

In dreams, you'll often skip from one scene to the next with little or no transition, or you might remember something that never happened. If you try to remember what just happened as a reality check, then you might realize that you were just in a completely different place, or you might not be able to remember anything at all from more than a couple minutes ago.

Examples of this reality check working

 * I was in a forest. Then I was in a kitchen. I didn't notice the change, and I started to get something to eat, but then I saw a dark green light flowing out of the microwave, reminiscent of a forest. I thought back to a few minutes ago and realized I was in that forest then, not this kitchen. I realized I must be dreaming.
 * I heard someone in my dream say the phrase, "What language do you dream in?", and I thought, "Hey, I can't just have pulled that from my head, it must be something I've recently heard!" I started remembering my previous "Waking Day", and I remembered that a friend told me that same phrase in school last day! And so I realised I was dreaming.

Examples of this reality check failing

 * I was in a parking lot near a big truck, and I thought it was mine. However, I remembered coming here on a bike, so I was beginning to think I was dreaming, but then I thought about it a bit more and I discovered a false memory of me coming here in the truck. Though I was still doubting it (I had the feeling it was a false memory, because I was quite sure I came on a bike), I lost the bit of lucidity I had.

Sueño lúcido/Test de Realidad/Memoria

title: Lucid Dreaming/Reality Checks/Memory


text:
User:Perl~enwikibooks/Fahrenheit 451/themes

big ==

$$Headline text$$#REDIRECT Insert text}}Subscript text
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=Themes=

One of the most obvious themes in the novel is how important it is for individuals to refrain from rushing through life. In essence, Bradbury makes the point that “you should stop to smell the roses” but more eloquently and meaningfully than this trite platitude is able to do. Bradbury’s futuristic society consists of many individuals who drive their cars (called beetles) at extremely high velocities, watch interactive TV at extremely high volumes, listen to in-ear radio devices much like an iPod, and rarely pay attention to the small things in life. Clarisse is an exception to this rule, but since she is killed by a car that was speeding down the road, she is nonetheless greatly impacted by this lifestyle.

Another prevalent motif is Bradbury’s opinion that abridged versions or summaries of books lead to the type of society that exists in his novel. In one of Beatty’s stories about how the world came to be the way it is, he says that great pieces of literature gradually became more condensed until they ceased to be substantial. This is similar to the previously discussed theme. Ironically, study-guides, like the one you're reading, may be an example of the same tendency.

The theme concerning mankind’s failure to learn from its past is more prevalent near the end of the novel. When the war starts, Granger compares this failure to the endless cycle that a phoenix goes through burning itself and rising from the ashes, but notes that humans, unlike the phoenix, are able to remember the stupid things that they did. Next (Conflicts) >


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User:Information Ecologist

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Information ecologist
I evolved into the role of Information Ecologist - now Professor of Information Ecology - at Information Habitat: Where Information Lives  in the spring of 1996, in response to a conception of information ecology as an embryonic holistic life science and operating system for sustainability and peace. This evolution took place in the context of the final stages of preparation for the 1996 Habitat II Conference in Istanbul, for which Information Habitat - an NGO in Special Consultative Status with the UN Economic and Social Council had built and managed the web site and the principal electronic mailing lists. The seeds of information ecology had been planted with the conceoption of Information Habitat: Where Information Lives in May 1990 at an interfaith Caring for Creation conference in preparation for the 1992 Earth Summit. in appreciation of the remarkable transformations taking place in the nature, magnitude and accessibility of information habitats in an era of microcomputers and information and communications technology and the recognition of information and information systems as rapidly evolving new life forms.

Information Habitat has pioneered the systematic use of information and communications technology in support of broad-based access to and exchange of information, plans and ideas throughout the preparation for the major series of UN Conferences from the 1992 Earth Summit in Rio de Janeiro to the 1996 Habitat II Conference, and in the follow-up to the resulting global agreement - especially through the UN Commission for Sustainable Development.

Currrent focus is on the development of an open source, common content interactive platform for the NGO Committee on Education of the CONGO - Conference Of Non-Governmental Organizations in Consultative Relationship with the United Nations - incorporating a supportive environment for Wiki spaces, blogs, podcasting, vblogs, etc., with a focus on the United Nations Decade of Education for Sustainable Development and the International Decade for a Culture of Peace. An initial component of the site incorporates an extensive hyperlinked collection - the first of its kind - of several hundred United Nations documents relating to sustainability, a culture of peace, water, human rights, etc. at http://www.un-documents.net

My life's work up to that time had prepared me for the profession of information ecologist. I had been headed for a promising academic career as a mathematical sociologist with degrees in mathematics and economics at Cambridge and social science research & methodology at Johns Hopkins. However I withdrew from academia in 1972 in the context of participation in the Vietnam Peace movement and concern as to the dominance of academia by a military-industrial complex.

I learned much about information ecology in more than thirteen years at the Baltimore City Jail - as librarian for eight and a half years, and the remaining five years an an administrative analyst - and in the course of thirty years of experience with advocacy & activist organizations that focused on peace, health, community development and interfaith dialogue at local, national and international levels.

The ecological dimensions of my training in information ecology have grown out of a love for the natural environment and my experiences as an organic gardener - with a passion for composting that I had learned as a child - combined with an appreciation of holistic processes. Through the recent discovery of and involvement in La Perla Gardens- beginning with an Independence Day Worm Feast, I have been able to reconnect to the earth in ways that have brought me great joy.

Since May, 1989, my attention had been focused on the preparations for the 1992 Earth Summit / UNCED, and on the vital role that information technology could play in support of broad-based participation of NGOs in the conference, and I had developed an outline proposal for an information, public participation and communications system that had led to the 1990 Earth Day launch of a "Global Environmental Network" by the UNCED Secretariat, whle as a Co-Chair of the Religious Outreach Committee for the 1990 Earth Day in Baltimore, organized a sunrise interfaith dedication of a fifth verse of the U.S. National Anthem at Fort McHenry, Birthplace of the Star-Spangled Banner -

Increasingly a focus has been towards gathering, compiling and organizing geographical information, including maps and satellite images. This has included a 1996 focus on the Mesopotamian Marshlands: Between the Rivers - A Cradle of Civilization in support of the New Eden Project - and the observation of  Mesopotamian Summer, with the purpose of engaging in dialogue and appreciative inquiry - inter alia making use of a Wiki platform - into the feasiblity of a holistic approach to restoring and regenerating the decimated Marshes, and of the development of an open source wireless Internet Protocol platform for a new knowledge-based civilization. I had begun working on several wikibooks related to the restoration of the Marshes and information ecology. however, much of what I had published has been deleted - although it could be easily regenerated. In the wake of the massve October 2005 Kashmir Earthquake the gathering and organizing of information, maps and satellite images expanded to addressing the needs and opportunities for open source platforms combined with handheld wireless devices in facilitating coordination of logistics and relief efforts. An immediate down-to-earth focus is on preparation for an interactive online learning environment, featuring a biodiversity resources map of La Perla Gardens intended to sere as a prototype for use by community gardens, parks, etc anywhere.

Although I have no recognized academic affiliation, I have begun to use the title of Professor of Information Ecology - using the dictionary definition of "professor" as one who professes - marking a new phase that will focus on teaching information ecology. Since 1996, I had been using the title Information Ecologist; during these eight years, my focus had been on development of the theory and practice of Information Ecology and believe it is now time for me to begin the task of teaching about information ecology.

Education

 * Whitgift School, Croydon, Surrey, UK. Croydon County Council Scholarship - 1956-1962

 * Corpus Christi College, Cambridge, UK. Open Exhibition in Mathematics - 1963-1966

 * Cambridge University, B.A. Honours in Mathematics and Political Economy, 1966

 * The Johns Hopkins University, Baltimore, MD, 1967-1972

 * Graduate Fellow in Social Relations

 * M.A. in Social Relations, 1972 - completed all requirements for Ph.D. except for thesis

 * Community College of Baltimore, Baltimore, MD. Continuing Education courses in Systems Analysis and Human Anatomy

Research

 * Quantitative Analysis of the French Revolution, Institute of Human Sciences, Boston College. Project Director: Gilbert Shapiro, funded by the National Science Foundation. Research Assistant. 1966.07 - 1967.06.

 * more coming soon.

 * detailed, lengthy cv, 2003

Publishing
While I have published many brief articles on the web as well as via many electronic mailing lists, most of my work in the area of print publication has been in nn editorial capacity, with a focus on the document's organizational coherence and from a concern with developing inclusive consensus-based documents.

 * Policy and Procedures Manual: Baltimore City Jail. . Baltimore, Maryland, 1984. (Editor and principal writer)

 * The Alternative Press Index . The Alternative Press Center, Baltimore Maryland. Designed the datataperfect database and WordPerfect Syles and Macros that were used to gnerate the body of the Alternative Press Index.

 * Queries on Unity with Nature . Friends Committee on Unity with Nature. Baltimore, Maryland, 1989. Republished in the United Nations Environment Programms's 1989 Environmental Sabbath
 * Report Card on Baltimore Elementary Schools . Citizens Planning and Housing Association, Baltimore, Maryland, 1990. Compiled and presented the quantitative information in the Report.

 * Network '92. Centre for Our Common Future, Geneva, Switzerland, 1991.04 - 1992.06. Distributed an eletronic edition of Network '92, the monthly newsletter with news and reports of preparations for the Earth Summit. Th electronic version was generally distributed - and received - approximately one month before the print edition arrived.

 * ''' ... more to come

 * Da Zi Bao: An Interactive Process . Environment Liaison Centre International, '92 Global Forum and International Synergy Institute. Paris, France; Washington, DC; Tucson, AZ, Sidney, Australia; New York, NY; Rio de Janeiro, Brazil. 1991-12 - 1992.06

 * The NGO Alternative Treaties and the NGO Treaty Process International NGO Forum, Ottawa, Canada, 1994. Editing and format; Three earlier editions of the Alternative Treaties published, from 1992.09

 * Agenda 21 & the Rio Agreements . United Nations Conference on Environment and Development, Rio de Janeiro, Brazil. French & Spanish versions published as zipped files; first html publication of Agenda 21; also distributed inexpensive diskette copies - including draft versions and background documents throughout the preparatory process.

 * The Habitat Agenda, 2nd United Nations Conference on Human Settlements. Istanbul, Turkey, June 14, 1996. Published on World Wide Web and via email list and diskette - in Engish, French & Spanish.

 * Toward Earth Summit II : NGO Recommendations for Actions and Commitments at Earth Summit II. New York, NY, 1997.

 * Petition for an Emergency UN Resolution on Iraq . Uniting for Peace Coalition, New York, NY 2003.05.01

 * UN Documents - Gathering a Body of Global Agreements, NGO Committee on Education, Conference of NonGovermental Organizations in Consultative Relations with the United Nations, New York, NY 2006.

Wikibooks in Development

 * Note: development of the wikibooks listed below is temporarily in abeyance, pending access to a wiki space that supports the database approach to the development of wikibooks that was a key contributing factor in the deletion of most of the materials in the initial drafts of tese wikibooks.

 * Information Ecology [] - the elements of information ecology, an evolving holistic life science for a knowledge-based universe that acknowledes in formation and information systems s evolving life forms, with vital significance for the continuity of intelligent life on Earth. Status: Extensive database-generated outline, some preliminary sections elaborated, and link to Information Habitat's information ecology achives.

 * Information Habitat: Where Information Lives a case study of the use of information and communications technology in support of broad-based NGO participation and access to and exchange of information by NGOs in the series of UN Global Conferences of the 1990s and the home of Information Ecology and the Light Cubes / Virtual Light and Colour Cubes.

 * Mesopotamian Marshlands - a holistic, watershed-based approach to the restoration of the Mesopotamian Marshlands, home of the cradle of civilization, and the lungs and digestive system of the Mesopotamian watershed, incorporating a wireless, Internet Protocol-based platform for the marshes, and for a knowledge-based platform for an Iraqi society. Initiated on Memorial Day, 2004.06.01.

 * Alice in Cyberwonderland . Preliminary draft of a modern-day update of Lewis Carroll's Alice in Cyberwonderland. The new version, in which Alice follows the White Rabbit through the screen of her new notebook computer, has also been writen under a pseudonym - John Doe. Like Rev. Charles Dodosn - Lewis Carroll's alter ego - is a mathematician - educated at Cambridge, instad of Dodoson's Oxford, and loves reading to, and playing with, young children.

 * Morphometrics Measurement of changes in shape of living organisms, with particular attention to measuring and analyzing past and future changes with espect to the Mesopotamian Marshes, the Shatt-al Arab / Arvand Rud watershed, information ecosystems and the field of morphometrics itself. Status. Initial opening page and outline, with some external links.

 * DataPerfect - coming soon - on open source curriculum in DataPerfect, a brilliant and exceptionally versatile DOS relational database companion of the classic WordPerfect for DOS. Status

 * Light Cubes: Elements of Light and Colour - coming soon - an open source curriculum in the Elements of Light and Colour and the transformative eye-opening properties of the Virtual Light and Colour Cubes - virtual cubes, with dimensions of red, green and blue, in which the colour at any point is equal to the sum of its red, green and blue coordiates, as expressed in the HTML expression #rrggbb.

Wiki profiles

 * Grandpa Ruh @ The Wealth of Networks

 * User:Information Habitat @ Wikipedia

 * Information Ecologist @ Metawiki

Other profiles

 * Grandpa Ruh @ Blogspot

 * Grandpa Ruh @ TakingITGlobal

 * Ruh Nabil @ Common Content
 * An information ecologist's weblog

 * Annotated chronology / detailed cv to 2003

Other web sites

 * Seasons of Peace Cooperation Circles

 * Information Habitat: Where Information Lives

 * Gandhi-King Season for Nonviolence

 * Light Cubes

 * }

title: User:Information Ecologist


text:
Using GNOME/Menus

A menu is a list of actions or commands. They maybe menus in menus (submenus) There are three main types of menu used in GNOME

 * 1) Panel menu bar
 * 2) Panel main menu
 * 3) Application menus

Back to contents page

title: Using GNOME/Menus


text:
Using GNOME/Menu bar

The Menu bar in GNOME is a item on the panel. It is split into two sections : Applications and Actions.

Applications is a menu of available applications installed, organized by category.

Actions is a list of actions available for the system. The actions are :
 * Run Application...
 * Search for files...
 * Recent Documents
 * Take Screenshot...
 * Lock Screen
 * Log out

title: Using GNOME/Menu bar


text:
Using GNOME/Browse folder

Browse Folder is a different way of exploring files. In this mode

 * There is only one window for file management
 * Navigation is done with navigation arrows
 * The location of the folder in the file system is displayed
 * There are special toolbar modes.

For users of GNOME prior to 2.6, this mode will be familiar to you. To use browse folder, right click a folder, then select "Browse Folder".

Tip : To use Browse Folder by default, set the following configuration key to true : /apps/nautilus/preferences/always_use_browser

title: Using GNOME/Browse folder


text:
Using GNOME/Configuration Editor

The Configuration Editor, technically known as GConfg-editor is a special tool to change hidden settings within GNOME. They are usually hidden because they are not missed by non-power users but power users may appreciate them.

The Configuration Editor is easy to get to grips with, yet learning all the Key's hard.

There are two ways to launch Configuration Editor.
 * 1) Menu, Preferences, Advanced, Configuration Editor.
 * 2) Type gconf-editor from Run Application.

The configuration editor screen

The screen is split in to three panes, key tree (left), key list (top right ), key info (bottom right).

Key Tree. There are four main key categories in the key tree.
 * apps
 * desktop
 * schemas
 * system

In each category there is a collection of folders which can contain sub folders and keys.

Keys each have a name, value and description. Make sure you try all the keys to see what they do. This guide has references to popular keys. Look out for them in Tip boxes!

title: Using GNOME/Configuration Editor


text:
Using GNOME/Terminology

This guide uses various technical terms. This chapter explains ones used.

 * 1) Keyboard
 * 2) Mouse
 * 3) Icons
 * 4) Tips and Warnings
 * 5) Other Jargon

Back to contents page

title: Using GNOME/Terminology


text:
Using GNOME/Applets

Using_GNOME >

An applet is a small program that sits and runs on the panel. This chapter is a guide to all the applets available for GNOME.

Accessories

 * Clock
 * Dictionary Lookup
 * Sticky notes
 * Stock ticker
 * Weather report

Actions

 * Force Quit
 * Lock
 * Log out
 * Run
 * Screenshot
 * Search
 * Show Desktop

Amusements

 * Fish
 * Geyes

Internet

 * Inbox monitor
 * Modem lights
 * Wireless link monitor

Multimedia

 * CD player
 * Volume Control

Utility

 * Battery Charge Monitor
 * Character Palette
 * Command line
 * Disk Mounter
 * Keyboard Accessibility Status
 * Notification Area
 * System Monitor
 * Window List
 * Window Selector
 * Workspace Switcher

Others

 * Launcher
 * Launcher from Menu
 * Main Menu
 * Menu Bar
 * Drawer

title: Using GNOME/Applets


text:
Using GNOME/Application windows

Applications in GNOME appear in Windows. Windows are usually box-shaped and can be manipulated.

Things that can appear as Windows include
 * Folders and Files in the File Manager.
 * Applications
 * Message boxes
 * Preference screens
 * Notes

Window layout.

By default, the following layout is used

 * 1) Menu
 * 2) Title
 * 3) Minimize
 * 4) Maximize
 * 5) Close.

title: Using GNOME/Application windows


text:
Python Programming/Data Types

Data types determine whether an object can do something, or whether it just would not make sense. Other programming languages often determine whether an operation makes sense for an object by making sure the object can never be stored somewhere where the operation will be performed on the object (this type system is called static typing). Python does not do that. Instead it stores the type of an object with the object, and checks when the operation is performed whether that operation makes sense for that object (this is called dynamic typing).

Built-in Data types
Python's built-in (or standard) data types can be grouped into several classes. Sticking to the hierarchy scheme used in the official Python documentation these are numeric types, sequences, sets and mappings (and a few more not discussed further here). Some of the types are only available in certain versions of the language as noted below.

 * boolean: the type of the built-in values  and  . Useful in conditional expressions, and anywhere else you want to represent the truth or falsity of some condition. Mostly interchangeable with the integers 1 and 0. In fact, conditional expressions will accept values of any type, treating special ones like boolean , integer 0 and the empty string   as equivalent to  , and all other values as equivalent to.

Numeric types:
 * int: Integers; equivalent to C longs in Python 2.x, non-limited length in Python 3.x
 * long: Long integers of non-limited length; exists only in Python 2.x
 * float: Floating-Point numbers, equivalent to C doubles
 * complex: Complex Numbers

Sequences:
 * str: String; represented as a sequence of 8-bit characters in Python 2.x, but as a sequence of Unicode characters (in the range of U+0000 - U+10FFFF) in Python 3.x
 * bytes: a sequence of integers in the range of 0-255; only available in Python 3.x
 * byte array: like bytes, but mutable (see below); only available in Python 3.x
 * list
 * tuple

Sets:
 * set: an unordered collection of unique objects; available as a standard type since Python 2.6
 * frozen set: like set, but immutable (see below); available as a standard type since Python 2.6

Mappings:
 * dict: Python dictionaries, also called hashmaps or associative arrays, which means that an element of the list is associated with a definition, rather like a Map in Java

Some others, such as type and callables

Mutable vs Immutable Objects
In general, data types in Python can be distinguished based on whether objects of the type are mutable or immutable. The content of objects of immutable types cannot be changed after they are created.

Only mutable objects support methods that change the object in place, such as reassignment of a sequence slice, which will work for lists, but raise an error for tuples and strings.

It is important to understand that variables in Python are really just references to objects in memory. If you assign an object to a variable as below, all you really do is make this variable (a, s, or l) point to the object (1, 'abc', ['a string', 456, ('a', 'tuple', 'inside', 'a', 'list')]), which is kept somewhere in memory, as a convenient way of accessing it. If you reassign a variable as below you make the variable point to a different object (newly created ones in our examples). As stated above, only mutable objects can be changed in place (l[0] = 1 is ok in our example, but s[0] = 'a' raises an error). This becomes tricky, when an operation is not explicitly asking for a change to happen in place, as is the case for the <tt>+=</tt> (increment) operator, for example. When used on an immutable object (as in <tt>a += 1</tt> or in <tt>s += 'qwertz'</tt>), Python will silently create a new object and make the variable point to it. However, when used on a mutable object (as in <tt>l += [1,2,3]</tt>), the object pointed to by the variable will be changed in place. While in most situations, you do not have to know about this different behavior, it is of relevance when several variables are pointing to the same object. In our example, assume you set <tt>p = s</tt> and <tt>m = l</tt>, then <tt>s += 'etc'</tt> and <tt>l += [9,8,7]</tt>. This will change <tt>s</tt> and leave <tt>p</tt> unaffected, but will change both <tt>m</tt> and <tt>l</tt> since both point to the same list object. Python's built-in <tt>id</tt> function, which returns a unique object identifier for a given variable name, can be used to trace what is happening under the hood.

Typically, this behavior of Python causes confusion in functions. As an illustration, consider this code:

This will give the above indicated, and usually unintended, output. <tt>myseq</tt> is a local variable of the <tt>append_to_sequence</tt> function, but when this function gets called, <tt>myseq</tt> will nevertheless point to the same object as the variable that we pass in (<tt>t</tt> or <tt>l</tt> in our example). If that object is immutable (like a tuple), there is no problem. The += operator will cause the creation of a new tuple, and <tt>myseq</tt> will be set to point to it. However, if we pass in a reference to a mutable object, that object will be manipulated in place (so <tt>myseq</tt> and <tt>l</tt>, in our case, end up pointing to the same list object).

Links:
 * 3.1. Objects, values and types, The Python Language Reference, docs.python.org
 * 5.6.4. Mutable Sequence Types, The Python Standard Library, docs.python.org

Creating Objects of Defined Types
Literal integers can be entered in three ways:
 * decimal numbers can be entered directly
 * hexadecimal numbers can be entered by prepending a 0x or 0X (0xff is hex FF, or 255 in decimal)
 * the format of octal literals depends on the version of Python:
 * Python 2.x: octals can be entered by prepending a zero ( 0 ) (0732 is octal 732, or 474 in decimal)
 * Python 3.x: octals can be entered by prepending a zero followed by the letter O (0o or 0O) (0o732 is octal 732, or 474 in decimal)

Floating point numbers can be entered directly.

Long integers are entered either directly (1234567891011121314151617181920 is a long integer) or by appending an L (0L is a long integer). Computations involving short integers that overflow are automatically turned into long integers.

Complex numbers are entered by adding a real number and an imaginary one, which is entered by appending a j (i.e. 10+5j is a complex number. So is 10j). Note that j by itself does not constitute a number. If this is desired, use 1j.

Strings can be either single or triple quoted strings. The difference is in the starting and ending delimiters, and in that single quoted strings cannot span more than one line. Single quoted strings are entered by entering either a single quote (') or a double quote (") followed by its match. So therefore 'foo' works, and "moo" works as well,     but 'bar" does not work, and "baz' does not work either. "quux '' is right out.

Triple quoted strings are like single quoted strings, but can span more than one line. Their starting and ending delimiters must also match. They are entered with three consecutive single or double quotes, so foo works, and """moo""" works as well, but '"'bar'"' does not work, and """baz ''' does not work either. '"'quux"'" is right out.

Tuples are entered in parentheses, with commas between the entries: Also, the parenthesis can be left out when it's not ambiguous to do so:

Note that one-element tuples can be entered by surrounding the entry with parentheses and adding a comma like so:

Lists are similar, but with brackets:

Dicts are created by surrounding with curly braces a list of key/value pairs separated from each other by a colon and from the other entries with commas:

Any of these composite types can contain any other, to any depth:

Null object
The Python analogue of null pointer known from other programming languages is None. None is not a null pointer or a null reference but an actual object of which there is only one instance. One of the uses of None is in default argument values of functions, for which see ../Functions. Comparisons to None are usually made using is rather than ==.

Testing for None and assignment:

Using None in a default argument value:

PEP8 states that "Comparisons to singletons like None should always be done with is or is not, never the equality operators." Therefore, "if item == None:" is inadvisable. A class can redefine the equality operator (==) such that instances of it will equal None.

You can verify that None is an object by dir(None) or id(None).

See also ../Operators/ chapter.

Links:
 * 4. Built-in Constants, docs.python.org
 * 3.11.7 The Null Object, docs.python.org
 * Python None comparison: should I use “is” or ==?, stackoverflow.com
 * PEP 0008 -- Style Guide for Python Code, python.org

Type conversion
Type conversion in Python by example:

Implicit type conversion:

Keywords: type casting.

Links:
 * 2. Built-in Functions # bool, docs.python.org
 * 2. Built-in Functions # list, docs.python.org
 * 2. Built-in Functions # float, docs.python.org
 * 2. Built-in Functions # int, docs.python.org
 * 2. Built-in Functions # set, docs.python.org
 * 2. Built-in Functions # str, docs.python.org
 * 2. Built-in Functions # type, docs.python.org
 * 2. Built-in Functions # tuple, docs.python.org

Exercises

 * 1) Write a program that instantiates a single object, adds [1,2] to the object, and returns the result.
 * 2) Find an object that returns an output of the same length (if one exists?).
 * 3) Find an object that returns an output length 2 greater than it started.
 * 4) Find an object that causes an error.
 * 5) Find two data types X and Y such that X = X + Y will cause an error, but X += Y will not.

title: Python Programming/Data Types


text:
Python Programming/Scoping

Variables
Variables in Python are automatically declared by assignment. Variables are always references to objects, and are never typed. Variables exist only in the current scope or global scope. When they go out of scope, the variables are destroyed, but the objects to which they refer are not (unless the number of references to the object drops to zero).

Scope is delineated by function and class blocks. Both functions and their scopes can be nested. So therefore

Now when this code is tested,

The name 'bar' is not found because a higher scope does not have access to the names lower in the hierarchy.

It is a common pitfall to fail to assign an object to a variable before use. In its most common form:

Here, to correct this problem, one must add y = [] before the for loop executes.

A loop does not create its own scope:

Keyword global
Global variables of a Python module are read-accessible from functions in that module. In fact, if they are mutable, they can be also modified via method call. However, they cannot be modified by a plain assignment unless they are declared global in the function.

An example to clarify:

Links:
 * 6.13. The global statement, docs.python.org
 * What are the rules for local and global variables in Python? in Programming FAQ, docs.python.org

Keyword nonlocal
Keyword nonlocal, available since Python 3.0, is an analogue of global for nested scopes. It enables a nested function to assign-modify even an immutable variable that is local to the outer function.

An example:

Simulation of nonlocal in Python 2 via a mutable object:

Links:
 * 7.13. The nonlocal statement, docs.python.org

globals and locals
To find out which variables exist in the global and local scopes, you can use locals and globals functions, which return dictionaries:

Write access to locals dictionary is discouraged by the Python documentation.

Links:
 * 2. Built-in Functions # globals, docs.python.org
 * 2. Built-in Functions # locals, docs.python.org

title: Python Programming/Scoping