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Suomen kieli käyttöön

This is the English version of the Finnish Book Suomen Kieli käyttöön (Finnish Language in Use).

The title and all chapters names parallel the original book to make it easy to navigate from the English and Finnish Books. This is done merely by changing the address from en.wikibooks.org/ etc.... to fi.wikibooks.org/ etc....

Also in development is a translation in Russian and soon other languages.

Finnish Language in Use (this book) has a companion reference book Finnish Language for Foreigners which provides information about the rules of grammar and pronunciation in the Finnish language.

Who is developing this book?
This book began life as a project run at Timali the adult education centre in Raisio, near Turku, in Western Finland. The Timali school teaches Finnish to more than one hundred foreign students learning the Finnish language every year.

We hope that other people in Finland and around the world will join us in this project to make this book the best possible place to learn Finnish on the World Wide Web.

Why is this book being developed?
Grammar: Learning Finnish requires the student to develop many levels of understanding of the language. It is not enough to arm oneself with a book on Finnish grammar and an English-Finnish dictionary to become a competent user of the language. Certainly, a Finnish grammar is essential, but it is not sufficient. There are many idiomatic forms and usages that do not fit a "rule book", which is essentially what a grammar is. So one has to learn the exceptions and special cases as well as the general rules.

Similarly with vocabulary. Most dictionaries are a compromise between what the user needs to know and the limitations forced on dictionary compilers by the physical size of the dictionary. For instance, a small dictionary might tell you (as mine did) that the translation for "goodbye" is "hyvästi". But it is quite wrong to use "hyvästi" in most circumstances! It actually means "goodbye" when you are likely never to see the person again! "Näkemiin" (till we see again) or "Hei Hei" (Bye-bye) or "Nähdään" (see ya) are much more common everyday ways of saying goodbye. Some basic books teaching Finnish to foreigners do have these details, but they suffer from the same restriction on size that dictionary compilers have.

An on-line book such as this has no such restriction. Physical size is not really a problem.

Linguistic constructions: Some things in Finnish are rather similar to English (for example past tense constructions), but there are many instances that are different. The participle constructions can seem quite strange and there are many instances of verb/noun constructions that the foreigner just has to learn. So for instance a person in Finland will "EAT his medicine" (not "TAKE his medicine" as in English), and will check in the paper to see what is "COMING FROM TV TONIGHT" (not to see what is "ON TV TONIGHT"). No dictionary or simple grammar book will tell you these things. We hope that this book will. In this respect this translation of "Suomen kieli käyttöön" will differ from the original Finnish book under development and from other translations such as that in Russian.

This book aims to close the gap between dictionaries and grammar books by providing a book with lots of examples of the language in everyday use. From newspaper and magazine articles, letters and e-mails, to spoken interview and chat room dialogues. The latter especially tend to contain lots of contractions and dialectical forms extensively found in the spoken language.

The ultimate aim is to provide people who are learning the Finnish language an understanding of how sentences are constructed, and how to determine the right case for a noun (not always easy for a person not used to using a language that has 15 different noun cases!), and how to understand and correctly use the various passive, active, infinitive and participle forms of verbs. On top of that, students will also be able to identify and learn the various forms of "rektio" (case form governance directed by a verb). These are undoubtedly the biggest problems faced by foreign learners of Finnish.

How is this achieved?
This book has been created on the Finnish Wikibooks site at Suomen kieli käyttöön. It has parallel translations on other Wikibooks sites. It contains real life Finnish texts and some audio material. These translation pages are created by students who are expected to cross-check each other's work, and we hope that students wherever in the world they are, will add new texts here (as well as on the Finnish Wikibook version, being careful of course not to breach anyone's copyright!) and that they will encourage their friends who speak Finnish fluently to help out and correct any mistakes, or highlight any matter that he or she may think is of interest to students developing this book. Of course there is no guarantee that these translations are error free at any given time but hopefully, as with other WIKI type projects, any errors will soon be ironed out by those who understand things better. Its a good idea therefore to create a log-in ID and put pages you have read to your watch-list so that you can see the changes as they are being made.

We hope students will place links from the Finnish pages to the versions they have translated.

Texts are graded for complexity. Thus it makes sense if you are complete beginner to start with texts at Level 1 and work your way through the levels. This grading is done by taking an overall look at the complexity of the texts and assigning a complexity level. Because the texts are mostly from real life, some complex language may occasionally be seen in lower graded texts.

Formal analysis of texts is encouraged to point out grammatical features and highlight the special usages of words in particular contexts. Students will raise questions about the texts on the discussion pages. They can communicate with each other through the use of the discussion pages and help each other to improve the translations and the analysis. If the students collectively cannot resolve the issue, the discussion may move to the equivalent page on the Finnish pages where questions can be asked in Finnish about the material. Finnish pages will be verified by Finnish speakers who hopefully can answer the questions raised. Readers of this book are therefore encouraged to log in and add pages they have read to their watchlists.

As readers get to understand how the language works, there will not always be the need to provide low level analysis of higher graded texts. Only the more complex elements will be analysed.

Register and Sign in regularly

 * This book is constantly being developed. New material will be added all the time.

 * Please create a log-in ID and remember your ID and password. You can set your language preferences here.

 * When you have read a page, made a translation, or raised a question on a discussion page, put the page onto your watchlist. You can only do this when you are logged in. When you log in next time, you can quickly see what changes have been made to the articles on your watch list.

Help develop the book

 * If you can improve on a page, please make the edit. It is very easy to edit pages.

 * If you have a query, raise it on the discussion page to discuss it with other students.

 * If you have some text you have analysed yourself, please publish it here and share your learning with others.

 * Please take care not to infringe other people's copyrights! Do not, for instance, publish exercises here from text books because that will certainly infringe copyright. Some original articles published here did originally carry copyright, but specific permission has been obtained in each case to publish them here.

Companion Reference Finnish Language for Foreigners
This book ties in with a reference book Finnish Language for Foreigners  which is being developed alongside. The reference book introduces the grammar and other features of Finnish, such as consonant gradation, pronunciation, and the main differences in the spoken and written language.

We also encourage the developers of this book to develop and use the Finnish section of Wiktionary as a useful on-line tool.

List of pages in development
Coffee Abroad

Reading
You can learn a lot by just reading. Here's why.

Level 1
uudet naapurit New neighbours

Level 2
kihlaus Engagement

Suot Swamplands

Rajalla At the border

Euroviisuvoitto Eurovision song contest champions

Conan O'Brien -haastattelu An interview with Conan O'Brien

Level 3
A home in Finland

Health care

Level 4
Financial guide

A cyclist in traffic

Level 6
Ilkka Jääskelainen (Finnish Pop Idol)

Level 1
The Best Romantic Comedy

Level 3
'kahvi ulkomailla Coffee Abroad

A Spa for Adults

Level 5
Miten erottuu

Level 6
Nopeusrajoitukset mitoitettu

Additional Grammar
Suomen kieli käyttöön Suomen kieli käyttöön Suomen kieli käyttöön

title: Suomen kieli käyttöön


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User:Andjam/Australia Olympics errata overview

While researching for the wikipedia article Australia at the Winter Olympics, a variety of sources were used.

Some of the sources disagreed with each other. Differences included placings, precise spellings of names, and the total number of competitors (ie the size of the field). Sometimes people who were disqualified have not been mentioned in various sources.

No definite conclusions have been made yet as to which source is right or wrong when they disagree.

Errata have been associated with books rather than web documents for technical reasons, not because web documents are assumed to be more reliable.

Books:

 * "Australia and the Olympic Games" by Harry Gordon. ISBN 0702226270 . Suspected errata: Errata/0702226270
 * "The Compendium: Official Australian Olympic Statistics 1896-2002" Australian Olympic Committee ISBN 0702234257 . Suspected errata: Errata/0702234257.
 * "Australians at the Olympics: A definitive history" by Gary Lester ISBN 0949853054 . Suspected errata: Errata/0949853054.

Web documents

 * "2002 Australian Winter Olympic Team Guide" . A PDF file published before the 2002 Winter Olympics, it appears to have been removed from the AOC web site in the lead up to the 2006 Winter Olympics, and therefore is available only by internet archive: http://web.archive.org/web/20030308012801/http://www.olympics.com.au/cp7/c9/webi/externaldocument/000114aq.pdf
 * "Winter Olympic Representatives 1924 - 2002" Ice Skating Australia
 * "Olympic Winter Games - Oslo 1952", published by the Organising Committee, Oslo 1952, pp. 228–33. PDF scan by the Amateur Athletics Foundation.

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


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Wikijunior:Kings and Queens of England/The Whole Book

=Introduction=

=The Anglo-Saxons (871-1016)=

=The Danes (1016-1042)=

=The Normans (1066-1154)=

=The Plantagenets (1154-1399)=

=The House of Lancaster (1399-1461, 1470-1471)=

=The House of York (1461-1470, 1471-1485)=

=The Tudors (1485-1603)=

=The Stuarts (1603-1649, 1660-1714)=

=The Hanoverians (1714-1901)=

=The House of Saxe-Coburg-Gotha (1901-1917)=

=The House of Windsor (1917 onwards)=

=Future monarchs=


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Wikijunior:Kings and Queens of England/Future monarchs

Prince William of Wales
Prince William of Wales was born at St. Mary's Hospital, Paddington on 21 June 1982. His parents are Charles, Prince of Wales and Lady Diana Spencer. He is next in the line of succession to the British throne.

On 1 March 1991 (St. David's Day), Prince William made his first official public appearance during a visit to Cardiff, the capital city of Wales. After arriving by plane, the eight-year-old prince was taken by his parents to Llandaff Cathedral. After a tour of the cathedral, he signed its visitors book, which showed that he was left-handed. Prince William went to the Mrs Jane Mynors' nursery school and the pre-prep Wetherby School both in West London, and later attended Ludgrove School in Berkshire. After passing an entrance exam he went on to attend Eton College in Berkshire. Whilst there he studied geography, biology and history of art at A-level.

Like a growing number of British teenagers, Prince William chose to take a gap year after finishing Eton College. He took part in British Army training in Belize. He spent the final stage of his gap year in southern Chile as a volunteer with Raleigh International. Pictures of the prince cleaning a toilet were broadcast around the world. After his gap year, Prince William attended the University of St Andrews in Fife, Scotland from 2001 until he was graduated in 2005. He started doing a degree course in Arts History, although he later changed his main subject to Geography and gained a Scottish Master of Arts degree with upper-second class honours. In January 2006, the prince began his cadet course at the Royal Military Academy Sandhurst to train as an Army Officer. William joined his brother who had been there since May 2005.

In July 2005, William carried out his first official engagements representing Elizabeth II, as Queen of New Zealand, at World War II commemorations in New Zealand. In September of the same year, it was announced that William will become president of The Football Association in May 2006 and patron to the UK charity Centrepoint, which works with homeless young people. In April 2011, he married Kate Middleton. In July 2013, the Duchess of Cambridge gave birth to their son, Prince George of Cambridge, third in line to the throne. The couple's second child, their daughter Princess Charlotte of Cambridge who is fourth in line to the throne, was born in May 2015. Prince Louis of Cambridge, the fifth in line to the throne, was born in April 2018.

Prince George
After William, Prince George of Cambridge will be the king of England. He was born on the 22nd of July, 2013. His full name is George Alexander Louis.


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Umbraco/Plugins And Extensions/Log Viewer

Log Viewer
Per Ploug Hansen from NetMedia has created an Umbraco log viewer which is available from his site


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Bartending/Cocktails/Sex on the Beach

Ingredients

 * 1½ oz. (40ml) Vodka
 * 3/4 oz. (20ml) Peach schnapps
 * 1½ oz. (40ml) Cranberry juice
 * 1½ oz. (40ml) Orange juice

Garnish
none

Glass

 * Highball Glass

Procedure

 * 1) Fill a highball glass with ice
 * 2) Add all ingredients.
 * 3) Stir.
 * 4) Serve

Variations
Shake with ice, strain into highball glass.

title: Bartending/Cocktails/Sex on the Beach


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Talk:Bartending/Cocktails/Sex on the Beach

anyone know what's up with the "units" and "standard drinks" measurements? hakamadare 13:22, 8 May 2006 (UTC)


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WebObjects/Web Services/Sending Large Data

Kristoff Cossement
Soap with mime attachments was indeed the way to go.

Remark: this only works with java 1.4.2_09 (I did not get it working with java 1.5.x)

For those who are interested I included some sample code on how to exchange large binary data between a java client and a webobjects server without taking all data in memory. You also need the java mail and java activation framework from sun.

Client.java
import javax.xml.soap.SOAPConnectionFactory; import javax.xml.soap.*; import javax.xml.transform.stream.*; import javax.xml.transform.*; import java.io.*; import org.apache.axis.attachments.AttachmentPart; import org.apache.axis.message.*; import javax.activation.DataHandler; import javax.activation.FileDataSource; import javax.xml.soap.SOAPElement; import java.util.*; import javax.mail.*; public class Client { public static File resize(String sPath) {     File file = new File(sPath); String endPoint = "http://localhost:55555/cgi-bin/WebObjects/project.woa/ws/FileUpload"; try{ SOAPConnection connection = SOAPConnectionFactory.newInstance.createConnection; SOAPMessage message = (javax.xml.soap.SOAPMessage)MessageFactory.newInstance.createMessage; SOAPPart part = message.getSOAPPart; SOAPEnvelope envelope = (org.apache.axis.message.SOAPEnvelope)part.getEnvelope; SOAPBody body = (org.apache.axis.message.SOAPBody)envelope.getBody; SOAPBodyElement operation = (org.apache.axis.message.SOAPBodyElement)body.addBodyElement(           envelope.createName("upload", "ns", "http://localhost:55555/cgi-bin/WebObjects/project.woa/ws/FileUpload")); operation.setEncodingStyle("http://schemas.xmlsoaporg/soap/encoding/"); DataHandler dh = new DataHandler(new FileDataSource(file)); AttachmentPart attachment = (org.apache.axis.attachments.AttachmentPart)message.createAttachmentPart(dh); SOAPElement filename = operation.addChildElement("filename",""); SOAPElement source = operation.addChildElement("source",""); message.addAttachmentPart(attachment); filename.addTextNode(file.getName); source.addTextNode(attachment.getContentId); SOAPMessage result = connection.call(message,endPoint); System.out.println(result); part = result.getSOAPPart; envelope = (org.apache.axis.message.SOAPEnvelope)part.getEnvelope; body = (org.apache.axis.message.SOAPBody)envelope.getBody; if(!body.hasFault) {         System.out.println("answer : "+body); }     }      catch(Exception e)      { e.printStackTrace; }     return null; }   public static void main(String[] args) { try { resize(args[0]); }     catch (Exception e) { System.out.println(e.getMessage); }   }  }

Webobjects Application .java
override dispatchRequest

public WOResponse dispatchRequest(WORequest request) {   WOResponse result = null; String sURI = request.uri; NSLog.debug.appendln("Accessing " + sURI); Pattern p = Pattern.compile("/ws/FileUpload"); Matcher m = p.matcher(sURI); if(m.find) {     String sContType = request.headerForKey("content-type"); p = Pattern.compile("multipart/related"); m = p.matcher(sContType); if(m.find) {       result = Dispatcher.handleFileUpload(request); }     else {       result = super.dispatchRequest(request); }   }    else {     result = super.dispatchRequest(request); }   return result; }

Dispatcher.java
// // Dispatcher.java // project // // Created by admin on 5/5/06. // Copyright 2006 __MyCompanyName__. All rights reserved. // import com.webobjects.foundation.*; import com.webobjects.appserver.*; import com.webobjects.eocontrol.*; import java.io.*; import java.util.regex.*; import org.w3c.dom.*; import javax.xml.transform.*; import javax.xml.transform.stream.*; import javax.xml.transform.dom.*; import javax.xml.parsers.*; import org.apache.axis.attachments.*; public class Dispatcher { public static WOResponse handleFileUpload(WORequest request) {     String sContType = request.headerForKey("content-type"); String sSoapXml = ""; InputStream requestStream = request.contentInputStream; String sTempDir = System.getProperty("java.io.tmpdir"); String timestamp =(new Long(System.currentTimeMillis)).toString; File fTempFile = new File(sTempDir+"/"+timestamp); File fSavedFile = new File(sTempDir+"/"+timestamp+".out"); try {       BufferedOutputStream fOut = new BufferedOutputStream(new FileOutputStream(fTempFile)); byte[] buffer = new byte[32 * 1024]; int bytesRead = 0; while ((bytesRead = requestStream.read(buffer)) != -1) {         fOut.write(buffer, 0, bytesRead); }       fOut.close; }     catch (Exception e)      { NSLog.debug.appendln(e.getMessage); }     try {       InputStream iStream = new FileInputStream(fTempFile); MultiPartRelatedInputStream mis = new MultiPartRelatedInputStream(sContType,iStream); DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance; Document doc = factory.newDocumentBuilder.parse(mis); sSoapXml = toString(doc); NSLog.debug.appendln("SOAP Envelope: " + sSoapXml); mis.close; iStream.close; Node nEnvelope = getNamedChildNode(doc,"Envelope"); if(null != nEnvelope) {         Node nBody = getNamedChildNode(nEnvelope,"Body"); if(null != nBody) {           NSArray nSubNodes = getElementChildNodes(nBody); if((null != nSubNodes) && (nSubNodes.count > 0)) {             Node nFileUpload = (Node)nSubNodes.get(0); nSubNodes = getElementChildNodes(nFileUpload); if((null != nSubNodes) && (nSubNodes.count > 1)) {               Node nFileName = (Node)nSubNodes.get(0); Node nData = (Node)nSubNodes.get(1); String sFileName = getTextFromNode(nFileName); String sFileMimeID = getTextFromNode(nData); fSavedFile = new File(sTempDir+"/"+sFileName); Pattern pattern = Pattern.compile("(boundary=\".+?\")"); Matcher match = pattern.matcher(sContType); if(match.find) {                 String boundary= match.group(1); String sSubContentType = "multipart/related; type=\"text/xml\"; start=\"<"+sFileMimeID+">\";  "+boundary; iStream = new FileInputStream(fTempFile); mis = new MultiPartRelatedInputStream(sSubContentType,iStream); try {                   BufferedOutputStream fOut = new BufferedOutputStream(new FileOutputStream(fSavedFile)); byte[] buffer = new byte[32 * 1024]; int bytesRead = 0; while ((bytesRead = mis.read(buffer)) != -1) {                     fOut.write(buffer, 0, bytesRead); }                   mis.close; fOut.close; }                 catch (Exception e)                  { System.out.println(e.getMessage); //throw new IOException(me + " failed, got: " + e.toString); }               }              }            }            }        }      }      catch(Exception e)      { e.printStackTrace; }     WOResponse result = new WOResponse; result.setContent( "\n"+         "\n"+          "\n"+          "\n"+          "true\n"+          "\n"+          "\n"+          ""); result.setHeader("text/xml; charset=utf-8","content-type"); return result; }   static public String toString(Document document) { String result = null; if (document != null) { StringWriter strWtr = new StringWriter; StreamResult strResult = new StreamResult(strWtr); TransformerFactory tfac = TransformerFactory.newInstance; try { Transformer t = tfac.newTransformer; t.setOutputProperty(OutputKeys.ENCODING, "utf-8"); t.setOutputProperty(OutputKeys.INDENT, "yes"); t.setOutputProperty(OutputKeys.METHOD, "xml"); //xml, html, text t.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4"); t.transform(new DOMSource(document.getDocumentElement), strResult); } catch (Exception e) { System.err.println("XML.toString(Document): " + e); }       result = strResult.getWriter.toString; }     return result; }   static public Node getNamedChildNode(Node n, String sChildNodeName) {     NodeList nl = n.getChildNodes; for(int i=0;i<nl.getLength;i++) {       Node s = nl.item(i); String sChild = s.getNodeName; if(sChildNodeName.equalsIgnoreCase(sChild) || sChild.endsWith(":"+sChildNodeName)) {         NSLog.debug.appendln("childnode = " + s.getNodeName); return s;       } }     return null; }   static public NSArray getElementChildNodes(Node n)    { NSMutableArray elements = new NSMutableArray; NodeList nl = n.getChildNodes; for(int i=0;i<nl.getLength;i++) {       Node s = nl.item(i); if(s.getNodeType == Node.ELEMENT_NODE) {         NSLog.debug.appendln("childnode = " + s.getNodeName); elements.addObject(s); }     }      return elements; }   static public String getTextFromNode(Node n)    { String text = ""; NodeList nl = n.getChildNodes; for(int i=0;i<nl.getLength;i++) {       Node s = nl.item(i); if(s.getNodeType == Node.TEXT_NODE) {         return s.getNodeValue; }     }      return text; } }


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Classical Mechanics/Lagrangian Exercises

Physics - Classical Mechanics

Prev Up Next

Exercises in setting up Lagrange functions and deriving the equations of motion
I recommend going through every exercise below (unless you know at once how to solve each of them). These exercises are not difficult but will give you experience in dealing with Lagrange functions. You do not really understand the Lagrangian formalism unless you can solve these standard problems without much effort.

Each of the following exercises poses the same questions: a) Introduce generalized coordinates and write down a Lagrange function for the system described below. b) Derive the Euler-Lagrange equations of motion. (It is not necessary to solve them!) Every situation is set up in the gravitational field near the Earth. All the mentioned sticks are massless and completely rigid. All the mentioned springs are massless and perfectly elastic (without friction) and have spring constant $$k$$. The lengths of springs at rest are given in the exercises.

1. A point mass $$m$$ hangs from the ceiling on a stick of length $$l$$. It can move only in the $$x-z$$ vertical plane.

2. Two point masses $$m$$ hang from the ceiling (far from each other) on two sticks of length $$l$$ each. They can both move only in the $$x-z$$ vertical plane.

3. Two point masses $$m$$ hang from the ceiling on two sticks of length $$l$$ each. They can both move only in the $$x-z$$ vertical plane. In addition, there is a spring with rest length $$l$$ connecting the two point masses. The points where the sticks are attached to the ceiling are at a distance $$l$$ from each other. (You may find this illustration useful.)

4. A point mass $$m$$ hangs from the ceiling on a stick of length $$l$$. Another point mass $$m$$ is attached to the first one with a stick of length $$L$$. Both masses can move only in the $$x-z$$ vertical plane.

5. A point mass $$m$$ hangs from the ceiling on a stick of length $$l$$. Another point mass $$m$$ is attached to the first one with a spring of rest length $$L$$. Both masses can move only in the $$x-z$$ vertical plane.

6. Two point masses $$m$$ are attached to the two ends of a stick of length $$2l$$. The midpoint of the stick is attached to the ceiling by a stick of length $$l$$. The entire arrangement can move only in the $$x-z$$ vertical plane.

7. A point mass $$m$$ is attached to the ceiling by a stick of length $$l$$. The point mass can move in all directions.

8. A point mass $$m$$ is attached to the ceiling by a spring of rest length $$l$$. The point mass can move in all directions.

9. Two identical carts of mass $$m$$ can roll without friction on a rail along the $$x$$ axis. They are connected by a spring of rest length $$l$$.

10. A cart of mass $$m$$ can roll without friction on a rail along the $$x$$ axis. A pendulum, consisting of a stick of length $$l$$ and a point mass $$m$$, is mounted rigidly on the cart and can move freely within the $$x-z$$ vertical plane.


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Classical Mechanics/Differential Equations

Physics - Classical Mechanics

Prev Up Next

A brief primer on differential equations
You may skip this primer and go to the next page if you can easily solve the following differential equations:

$$\frac{dx(t)}{dt}=4x+8t,\quad x(0)=0$$

$$\frac{d^2x(t)}{dt^2}+15x(t)=10,\quad x(0)=1,\quad\dot x(0)=0$$

$$\frac{dx(t)}{dt}=3t\sqrt x,\quad x(0)=1$$

Integration
Integration is the operation which is inverse to differentiation. This operation is very important for theoretical physics, and you should become familiar with computing integrals.

Definite integrals are written as follows: $$\int\limits_a^b f(x)dx$$. (There is really no separate concept of an "indefinite integral." The notation $$\int f(x)dx$$ is merely the shorthand for $$\int\limits_{x_0}^x f(x')dx'$$, where $$x_0$$ is not used in later calculations and/or is chosen for convenience in some natural way.)

Some basic integrals:

$$ \int f(ax)dx=\frac{1}{a}\int f(x)dx;\quad\int t^ndt=\frac{t^{n+1}}{n+1};\quad\int e^xdx=e^x;\quad\int\cos(x)dx=\sin(x); $$$$ \int\frac{dx}{x}=\ln(x);\quad\int\frac{dx}{1+x^{2}}=\arctan(x);\quad\int\frac{dx}{\sqrt{1-x^2}}=\arcsin(x)$$

Substitution of variable: introduce $$x=g(z)$$, where $$g(z)$$ is a function: $$\int f(x)dx=\int f(g(z))\frac{dg(z)}{dz}dz$$ Examples: $$\int\frac{dx}{1+x}=\ln(1+x)$$$$\int\frac{dx}{x^2}\sin\left(\tfrac{1}{x}\right)=\cos\left(\tfrac{1}{x}\right)$$

Integration by parts: $$\int\limits_a^b f(x)g'(x)dx=f(x)g(x)\bigg|_a^b-\int\limits_a^b f'(x)g(x)dx$$ For example, (here we do not write the limits of integration): $$\int\ln(x)dx=\int(x)'\ln(x)dx=x\ln(x)-\int x\ln'(x)dx=x\ln(x)-x$$

Note: trigonometric functions are sometimes more conveniently written in terms of complex exponentials (using the Euler formula): $$\cos(x)=\frac{e^{xi}+e^{-xi}}{2};\quad\sin(x)=\frac{e^{xi}-e^{-xi}}{2i};\quad e^{xi}=\cos(x)+i\sin(x)$$

Exercise:

Compute the following indefinite integrals. Test yourself!!!!!!
 * $$\int e^{2x}\sin(x)dx=$$
 * $$\int t^2\sin(t)dt=$$
 * $$\int\sin^2(x)dx=$$
 * $$\int\frac{dx}{\sqrt{2x+1}}=$$
 * $$\int x\sqrt{3x+1}dx=$$
 * $$\int \sqrt{\tan(x)}dx=$$

General solutions and particular solutions
In this section, differential equations are written for unknown function $$x(t)$$. Derivatives are denoted by overdots: $$\dot{x}\equiv\frac{dx}{dt}$$, $$\ddot{x}\equiv\frac{d^{2}x}{dt^{2}}$$ , etc.

The general solution of a differential equation is a function that solves the equation and contains arbitrary constants. For equations with first derivatives (first-order equations) there is only one constant; for second-order equations there are two constants, etc.

Examples:

where $$A$$ is an arbitrary constant. This has two solutions, $$\lambda=-1$$ and $$\lambda=-4$$. So the general solution is $$x(t)=Ae^{-t}+Be^{-4t}$$.
 * Find the general solution of the equation $$\dot{x}(t)=0$$ . Answer: $$x(t)=A$$ ,
 * Find the general solution of $$\dot{x}=2$$ . Answer: $$x(t)=A+2t$$.
 * Find the general solution of $$\dot{x}=4t+\cos(2t)$$ . Answer: $$x(t)=A+2t^{2}+\frac{1}{2}\sin2t$$.
 * Find the general solution of $$\dot{x}+x=0$$ . Answer: $$x(t)=Ae^{-t}$$.
 * Find the general solution of the second-order equation $$\ddot{x}=0$$ . Answer: $$x(t)=A+Bt$$.
 * Find the general solution of $$\ddot{x}+7x=0$$ . Answer: $$x(t)=A\cos(t\sqrt7)+B\sin(t\sqrt7)$$.
 * Find the general solution of $$\ddot{x}-7x=0$$ . Answer: $$x(t)=Ae^{t\sqrt7}+Be^{-t\sqrt7}$$.
 * Find the general solution of $$\ddot{x}+5\dot{x}+4x=0$$ . Solution: we look for $$x(t)=Ae^{\lambda t}$$ . Then $$\lambda$$ must be such that $$\lambda^2+5\lambda+4=0$$.

Exercises:

Find the general solution of the following equations.
 * $$\dot x=2x$$
 * $$\ddot{x}=3t+e^{-t}$$
 * $$\ddot{x}=\dot{x}$$
 * $$\ddot{x}=-10x$$
 * $$\ddot{x}=-2006\dot{x}+2006x$$

Particular solutions are selected from general solutions by conditions, such as the initial conditions: $$\ddot{x}=1,\quad x(0)=1,\quad\dot{x}(0)=2.\quad(1)$$ The general solution of $$\ddot{x}=1$$ is $$x(t)=A+Bt+\frac{t^2}{2}$$. The conditions $$x(0)=1$$, $$\dot{x}(0)=2$$ are satisfied only if $$A=1$$ , $$B=2$$. Therefore, the particular solution of equation (1) is $$x(t)=1+2t+\frac{t^2}{2}$$.

To find particular solutions, we first find the general solution with arbitrary constants and then determine the values of these constants using the initial conditions.

Exercises:

Solve the following equations with initial conditions. Plot the resulting functions $$x(t)$$.

 * $$\dot{x}+3x=0,\quad x(0)=2$$
 * $$\dot{x}-x=0,\quad x(2)=1$$
 * $$\ddot{x}-4x=0,\quad x(0)=1,\quad\dot{x}(0)=1$$
 * $$\ddot{x}-4t=0,\quad x(0)=1,\quad\dot{x}(0)=1$$

Boundary-value problems are differential equations with conditions at different points. Note: There are usually infinitely many functions that solve a differential equation. The general solution represents all these functions by means of a formula with arbitrary constants. A particular solution is selected by conditions, and one needs as many conditions as unknown constants. So, e.g. for a second-order differential equation, there are two arbitrary constants, and one needs two conditions to specify a unique solution. Instead of specifying two conditions conditions at the same time, such as $$x(0)=\dot x(0)=0$$, one can specify two conditions at different times, e.g. $$x(0)=1,x(1)=2$$. Such conditions are called boundary conditions.

Exercises:

Solve the following boundary-value problems. Hint: The last two equations have tricky boundary conditions!
 * $$3\ddot{x}+4x=0,\quad x(0)=0,\quad x(2)=5$$
 * $$\ddot{x}=4e^{-t},\quad x(0)=1,\quad x(1)=0$$
 * $$\ddot{x}+4x=0,\quad x(0)=0,\quad x(\pi)=\pi$$
 * $$\ddot{x}+x=0,\quad x(0)=2\pi,\quad x(2\pi)=2\pi$$

Some simple inhomogeneous equations
Equations of the form $$\dot{x}=Bx$$ have the general solution $$x(t)=Ae^{Bt}$$. What about $$\dot{x}=Bx+10$$ ? The general solution is $$x(t)=Ae^{Bx}+\frac{10}{B}$$. How to guess? Write $$x(t)=Ae^{Bt}+C$$ and substitute; then find the correct value of $$C$$.

Exercises:

Solve the following equations.
 * $$\dot x+3x=2,\quad x(0)=1$$
 * $$\ddot{x}+5\dot x+4x=8,\quad x(0)=2,\quad\dot x(0)=0$$
 * $$2\ddot{x}+18x=-1,\quad x(1)=1,\quad\dot x(1)=0$$
 * $$\ddot{x}+9\dot x=-2,\quad x(0)=0,\quad\dot x(0)=3$$

Hint: In the last equation, replace $$\dot x(t)$$ by an unknown function $$v(t)$$.

Similarly, $$\ddot{x}+\omega^2x=0$$ have the general solution $$x(t)=A_1\cos(\omega t)+A_2\sin(\omega t)$$. What about $$\ddot{x}+\omega^2x=A+Bt$$ ? Write $$x(t)=C_1+C_2t$$ and find the correct values of $$C_1$$ and $$C_2$$, then add the general solution. The result is $$x(t)=(A+Bt)\omega^{-2}+A_1\cos(\omega t)+A_2\sin(\omega t)$$.

Note that in every case the general solution of the equation without the right-hand side (the homogeneous equation) is added to a guessed solution of the equation with the right-hand side (the inhomogeneous equation). This is the general principle when dealing with such equations.

Exercises:

Solve the following equations:

 * $$\ddot{x}+2x=3t-1,\quad x(0)=\dot{x}(0)=0$$
 * $$\ddot{x}-4x=t^{2}-4t,\quad x(0)=\dot{x}(0)=0$$
 * $$\ddot{x}+\dot{x}+x=t^3+t^2+t,\quad x(0)=\dot{x}(0)=0$$

Method of "variation of constants"
What about $$\dot{x}=Bx+f(t)$$, where $$f(t)$$ is some more complicated function? These are solved with the method of variation of constants. The solution is found as $$x(t)=A(t)e^{Bt}$$, where $$A(t)$$ is an unknown function. Substituting into $$\dot{x}=Bx+f(t)$$, we have $$\dot{A}e^{Bt}+BAe^{Bt}=BAe^{Bt}+f(t)$$ therefore the function $$A(t)$$ satisfies the equation $$\dot{A}=e^{-Bt}f(t)$$. Its general solution is $$A(t)=\int\limits_{t_0}^t e^{-Bt_1}f(t_1)dt_1$$ where $$t_0$$ is an arbitrary constant. Therefore, the general solution for $$x(t)$$ is $$x(t)=e^{Bt}\int\limits_{t_0}^t e^{-Bt_1}f(t_1)dt_1$$ This can be also rewritten as $$x(t)=Ae^{Bt}+e^{Bt}\int\limits_0^t e^{-Bt_1}f(t_1)dt_1=Ae^{Bt}+\int\limits_0^t e^{B(t-t_1)}f(t_1)dt_1$$ where now $$A$$ is an arbitrary constant.

Example:

Solve $$\dot{x}+x=t$$. Solution: $$x(t)=A(t)e^{-t}$$ ; the function $$A(t)$$ is found from $$\dot{A}=te^t$$, so $$A(t)=\int te^t dt=te^t-e^t+C$$. So the general solution is $$x(t)=Ae^{-t}=t-1+Ce^{-t}$$. We could guess this solution by substituting $$x(t)=C_1t+C_2+Ae^{-t}$$ and finding the correct values $$C_1$$, $$C_2$$.

Exercises:

Solve the following equations with initial or boundary conditions.

 * $$\dot{x}-2x=3t^{2}-2t,\quad x(0)=1$$
 * $$\dot{x}+2x=e^{-t}\quad x(0)=1$$
 * $$\dot{x}+x=e^{-t}\quad x(0)=1$$

More general equations: $$\dot{x}-f(t)x=0\quad\Rightarrow\quad x=Ae^{\int f(t)dt}$$ For example: $$\dot{x}+2tx=0$$ has the general solution $$x(t)=Ae^{-t^2}$$.

Exercises:

Find the general solution of the following equations.
 * $$\dot{x}+t^2x=0$$
 * $$\dot{x}+e^tx=e^t$$

Another general formula is $$\dot{x}-f(t)x=g(t)\quad\Rightarrow\quad x=Ae^{\int\limits_0^t f(t_1)dt_1}\int\limits_0^t g(t_1)e^{-\int\limits_0^{t_1} f(t_2)dt_2}dt_1$$ This can be obtained by "variation of constant" in the solution $$Ae^{\int f(t)dt}$$.

Method of "separation of variables"
Another useful method applies to differential equations of the form $$\dot{x}=f(x)g(t)$$ For example, the differential equations $$\dot{x}=x^2t^2$$ and $$\sqrt{x}\dot{x}=\cos(t)$$ are of this form. To solve these equations, we use the trick called "separation of variables." We look for the solution of the form $$F(x)=G(t)$$, where $$F$$ and $$G$$ are some functions. If the solution were in this form, then $$\frac{d}{dt}F(x)=\frac{d}{dt}G(t)$$, which is the same as $$(dF/dx)\dot{x}=dG/dt$$. This should be equivalent to the original differential equation $$\dot{x}=f(x)g(t)$$. Therefore, $$\frac{dF(x)}{dx}=\frac{1}{f(x)},\quad\frac{dG(t)}{dt}=g(t)$$ These equations are easy to solve: $$F(x)=\int\frac{dx}{f(x)},\quad G(t)=\int g(t)dt$$ We can compute these functions and find the general solution of the original equation in the following implicit form: $$\int\limits_{x_0}^x \frac{dx}{f(x)}=\int\limits_{t_0}^t g(t)dt$$ Here, $$x_0$$ and $$t_0$$ are arbitrary constants of integration. This solution satisfies the initial condition $$x(t_0)=x_0$$.

Example:

Consider the equation $$\dot{x}=x^2t^2$$. We write $$\frac{\dot{x}}{x^2}=t^2\quad\Rightarrow\quad\int\frac{dx}{x^2}=\int t^2dt\quad\Rightarrow\quad -\frac{1}{x}+C=\frac{t^3}{3}\quad\Rightarrow\quad x(t)=\frac{1}{C-\frac{t^3}{3}}$$ Note that only one constant of integration is necessary, despite the presence of two "indefinite integrals".

Exercises:

Find the general solution of the following equations.
 * $$\dot{x}=\frac{x}{t}$$
 * $$\frac{dy(x)}{dx}=\frac{1+y}{1+x}$$
 * $$\sqrt{x(t)\frac{dx(t)}{dt}}=\frac{1}{5t}$$

Miscellaneous cases when solutions are guessed
One case is second-order equations with "source" (i.e. with nonzero function in the right hand side). We need to guess a solution of the inhomogeneous equation. We guess the solution by writing an ansatz with unknown coefficients. Here are some examples: $$\ddot{x}+x=\cos(2t)\Rightarrow x(t)=C_{1}\cos(2t),\quad\textrm{then~find~}C_1$$

$$\ddot{x}+4\dot{x}+3x=\sin(t)\Rightarrow x(t)=C_1\sin(t)+C_2\cos(t),\quad\textrm{then~find~}C_{1,2}$$

$$\ddot{x}+x=\sin(t)\Rightarrow x(t)=C_1t\cos(t),\quad\textrm{then~find~}C_1$$ Note: in the last example, we need a term $$t\cos t$$ because $$\sin(t)$$ and $$\cos(t)$$ are already solutions of the homogeneous equation!

Another example: $$\ddot{x}+2\dot{x}+x=0$$ We look for solutions in the form $$x(t)=e^{\lambda t}$$, find $$\lambda^2+2\lambda+1=0$$ and only one root $$\lambda=-1$$. Then we use a special trick: the general solution is not $$Ce^{-t}$$ but $$x(t)=C_1e^{-t}+C_2te^{-t}$$.

Exercises:

Solve the following equations.
 * $$\ddot{x}+4x=\sin(t)+1,\quad x(0)=\dot{x}(0)=1$$
 * $$\ddot{x}+4x=\sin(2t)+1,\quad x(0)=\dot{x}(0)=1$$
 * $$\ddot{x}-4\dot{x}+4x=2,\quad x(0)=\dot{x}(0)=1$$

Systems of differential equations: for example, $$\dot{x}=y,\quad\dot{y}=2x$$ may be solved either by differentiation: $$\ddot{x}=\dot{y}\quad\Rightarrow\quad\ddot{x}=2x$$, or by guessing the solution in the form $$x(t)=C_1e^{\lambda t}$$ , $$y(t)=C_2e^{\lambda t}$$.

Note: Since these equations are linear, you should add all the possible pieces of the general solution with different values of $$\lambda$$.

Exercise:

By guessing the solution in the form $$x(t)=C_1e^{\lambda t},y(t)=C_2e^{\lambda t}$$, find the general solution of the system $$\ddot{x}+x=-y,\quad\ddot{y}+y=3x$$


text:
User talk:Vaughano~enwikibooks

Your account will be renamed
Hello,

The developer team at Wikimedia is making some changes to how accounts work, as part of our on-going efforts to provide new and better tools for our users like cross-wiki notifications. These changes will mean you have the same account name everywhere. This will let us give you new features that will help you edit and discuss better, and allow more flexible user permissions for tools. One of the side-effects of this is that user accounts will now have to be unique across all 900 Wikimedia wikis. See the announcement for more information.

Unfortunately, your account clashes with another account also called Vaughano. To make sure that both of you can use all Wikimedia projects in future, we have reserved the name Vaughano~enwikibooks that only you will have. If you like it, you don't have to do anything. If you do not like it, you can pick out a different name.

Your account will still work as before, and you will be credited for all your edits made so far, but you will have to use the new account name when you log in.

Sorry for the inconvenience.

Yours, Keegan Peterzell Community Liaison, Wikimedia Foundation 23:49, 17 March 2015 (UTC)

Renamed
 This account has been renamed as part of single-user login finalisation. If you own this account you can |log in using your previous username and password for more information. If you do not like this account's new name, you can choose your own using this form after logging in: . -- Keegan (WMF) (talk) 05:37, 19 April 2015 (UTC)

title: User talk:Vaughano~enwikibooks


text:
Cookbook:Potatoes with Green Sauce

Green sauce is a dish that originates from the Frankfurt/Main region of Germany.

Ingredients

 * 3–4 cups (200 g / 7 oz per cup) sour cream
 * Milk
 * 1 tbsp sunflower oil (or other oil of neutral taste)
 * 2 tsp lemon juice
 * 4 hard-boiled eggs
 * 10–15 large potatoes
 * 1–1½ empty sour cream cups filled with dill
 * 1–1½ empty sour cream cups filled with other mixed herbs (e.g. chives, parsley, onion leaves, lemon balm, burnet, a small amount of sorrel if available)

Procedure

 * 1) Combine sour cream, oil, and lemon juice. Add milk until the mixture takes the consistency of a thick sauce.
 * 2) Mix herbs well, and mix them into the sauce.
 * 3) Cut hard-boiled eggs to small pieces and add them to the sauce along with some salt and pepper.
 * 4) Leave the sauce in the fridge for about 1–1½.
 * 5) Boil potatoes and serve hot with the cold sauce. More hard-boiled eggs can also be served along with this.

title: Cookbook:Potatoes with Green Sauce


text:
Umbraco/Samples and Articles/Templates/ValidateInput

Validating user input
When creating Umbraco document types you can validate content entry by using regular expressions in the Validation field.

Examples
Input must be between 5 and 10 characters:

^.{5,10}$


text:
Ancient History/Americas/Incan Empire

 * 1) /Inca mythology/
 * 2) /Emergence and expansion/
 * 3) /Spanish conquest and Vilcabamba/
 * 4) /After the Spanish conquest/

title: Ancient History/Americas/Incan Empire


text:
Ancient History/Greece/Greek Boats

Greek boats had two or three sails depending on the size of the craft. These boats were made out of large pieces of hard wood; these boats were large for the time but only could carry 100 – 150 kg of stone used to make statues. The usual items carried on the boats were construction supplies to build houses, war supplies such as iron, bronze, etc. the Greeks also carried lots of food, the most items they would trade were almonds,. Other objects they would carry were fish, olives, barley and other substances they would carry the substances over water by putting them in urns and putting a wax seal food.

There was a special road called the “Diolkos” it was a special road because it connected two seas so people would be able to travel to the other seas without getting a different boat, the length of this road was 175 km an anonymous writer said that after it was built it started to turn green because of the seaweed and barnacles laying on it because no one would clean it. This road started at one sea and ended at the other. What would happen was they would put this boat on a trailer pulled by three oxen they would then pull it across to the other sea.

To transport objects and themselves on land they would use wooden carts to pull themselves around the city or even their village. Now to pull the carts they would use animals, it was much easier to use pack animals because they would only have to control one for the others to follow. These animals could pull up to 100 kg. With the larger animals like oxen and cattle they could carry up to 500 kg. To build roads, not that they usually did because they thought it would be easier for their enemies to invade the area they would use stone or dirt to pave the area, the city would only do this if the area was based on trade. The fact was the poor people walked while the rich people used carts.

Transportation was a very important thing in ancient Greece. The people based their whole civilization on boat transportation.

title: Ancient History/Greece/Greek Boats


text:
Wikibooks:Administrators

Administrators, or "sysops", are Wikibookians who are generally well-known and trusted in the community, and who have had certain restrictions lifted at wikibooks. Administrators have the added abilities of being able to delete pages and block users for a specified period of time. Administrators are not granted any extra authority; they must follow all policies. They may grant the uploader, importer and reviewer flags.

Bureaucrats are administrators with extra tools responsible for judging community consensus in the granting of advanced access rights. They are able to create new administrators, bureaucrats and switch the bot flag. In certain cases, global rights holders may request a bureaucrat to determine whether a request should be processed. For example, a Global Renamer may check with a bureaucrat that a new username is acceptable.

Becoming an Administrator
Administrators will only be created after a discussion at Requests for permissions results in a consensus of acceptance. Wikibookians may either request permissions themselves, or be nominated by another. A user nominated to become an administrator must accept the nomination explicitly, either on Requests for permissions or on their user talk page before the discussion begins.

Discussion about the creation of a new administrator should follow the rules found at Decision making. Creating an administrator is a "high-impact" situation.

Only a bureaucrat has the privileges to create a new administrator, and they will use their judgment as to whether a consensus on the matter has been reached. If they do not believe a strong consensus has been reached, they will not create the administrator. Once an administrator has been created, they may not have the rights removed, even if the privileges have been granted in error, unless there has been a further discussion with consensus to remove the rights. If no bureaucrat is available to create an administrator, but consensus has been reached on the matter, users may post a request at Requests for permissions, where a steward may grant the permissions. Users are not allowed to ask the stewards for permissions if consensus has not been reached at Requests for permissions.

While there are no specific requirements to becoming an administrator, they should be "well-known and trusted" members of the community, and expected to know the Wikibooks policy, especially the deletion policy. Also, because administrators are able to block users, they are expected to be familiar with the process of blocking a user. Administrator rights will be removed if the editor is inactive for a year.

Becoming a Bureaucrat
Bureaucrats are created in the same manner as administrators. Prospective bureaucrats can either request the permissions, or they can be nominated (and must explicitly accept the nomination). Creating a new bureaucrat is a more weighty discussion than the creation of an admin, and therefore users should take it more seriously. An election for a new bureaucrat must be advertised in the reading room, and possibly on the bulletin board as well. Bureaucrats can be created by other bureaucrats, or the stewards at meta. It is not permissible to request bureaucrat permissions on meta if consensus has not been reached at Requests for permissions.

Candidates for Bureaucrats must currently be Administrators. There are no other specific requirements on creating new bureaucrats, although candidates are generally expected to be active Wikibookians, and well-respected admins.

Becoming a CheckUser
CheckUser rights provide an Administrator with additional tools for fighting vandalism. These tools allow an Administrator to see a Wikibookian IP address, in order to identify and combat disruption of the wiki.

Candidates for CheckUser must currently be Administrators, they can be nominated or request the rights, on Requests for permissions. There is no explicit requirement on the number of contributions, or activity here at Wikibooks, but it is expected that the candidate will be a noted active vandalism fighter. As with any request for permission, if the candidate is nominated, there must be an explicit acceptance for the vote to continue.

CheckUser rights can only be granted by stewards. Stewards may not be contacted to grant these rights unless consensus has been reached at Requests for permissions. The stewards may impose additional restrictions on the creation of CheckUsers, over which Wikibooks policy has no say. Access to the CheckUser tool is governed by the Wikimedia Foundation via the CheckUser Policy and requires that users who would like to become a CheckUser, be 18 years or older. Certain permissions (notably CheckUser and Oversight) additionally require users to sign a confidentiality agreement.

Removing an Administrator/Bureaucrat
Administrative tools can be removed in the same manner in which they are granted: a nomination for removal, or "de-adminship", at Requests for permissions and a consensus discussion to remove administrative powers from the offending admin. Sysops who do not meet any activity expectations (detailed below), or those who break policy, or those who abuse their powers, can be nominated for de-adminship at the Requests for permissions page. Broken expectations, policy violations, or abuses should be noted in the nomination, so that all users can examine the evidence and make a decision on the matter.

As helpful members of the community, Wikibooks administrators are expected to provide the community with timely assistance when needed or requested and maintain a general understanding of current Wikibooks environment and policies. Sysops who are especially inactive, specifically for at least one year or longer, can be removed without a consensus discussion. Users who are inactive for a year must still be nominated for de-adminship on Requests for permissions, and the time of their absence must be clearly noted. De-adminship in cases of absence for one year or more will take place at least one month after nomination on Requests for permissions. The inactive sysop will be contacted both on his/her talk page and e-mail address (if available) to contest the nomination.

Sysops requesting de-adminship themselves will have that request granted immediately, not being subject to community approval. Should a sysop have his/her privileges removed, the user may re-apply for adminship at a later date without prejudice.

Expectations
Administrators (and bureaucrats) have certain expectations on them. If an administrator doesn't live up to these expectations, they can be nominated for de-adminship. Admins who do not meet these expectations are not automatically removed: They must be nominated on Requests for permissions, and the discussion must reach consensus on the matter to remove the admin.

 * 1) Administrators are expected to be active (see sysop activity on Wikibooks). There are no hard and fast definitions on what it means to be "active" but the general expectation for nomination of desysopship is the lack of activity for a year. Administrators who are not using privileges, those privileges provided by the community due to the user's knowledge and activity, do not need to continue having them. Administrators do not have a "lifetime membership" and are expected to continually use their tools for the good of the community.
 * 2) Administrators are expected to follow Deletion policy. Administrators do not get to make unilateral decisions concerning page deletion, especially in controversial cases. Pages should not be deleted unless they are candidates for speedy deletions or if there has been a consensus discussion reached about the page on Requests for deletion. Deleting pages without following policy is a major problem and can be very disruptive to the community.
 * 3) Administrators are expected to follow applicable policies concerning blocking users and IP addresses. "Infinite" blocks should not be employed unless specifically warranted. Legitimate users should not be blocked unless they are demonstrably disruptive to the community. If an admin blocks a legitimate user for no good reason that is a major disruption and a violation of this policy
 * 4) Administrators are expected to know and understand the uses of protected pages, and not to abuse this privilege. Protecting and unprotecting pages without proper justification is against policy and prevents users from editing normally. Policies concerning semi-protection must also be understood and properly employed.

Administrators are just regular users, and they can be reprimanded as usual if they are disruptive, if they vandalize, etc.

Blocking users
If a user is clearly malicious or here for no reason besides to make trouble, they should be blocked. New users who are disruptive, but not maliciously so can receive short-term blocks to cool down. Administrators are trusted to use their judgment in determining whether a user deserves to be blocked and, if so, for how long. If it's not clear, discuss it at Reading room/Administrative Assistance.

Users who make particularly distasteful edits, and sock puppets of known serial vandals should be blocked permanently.

IP blocks
Open proxy IP addresses can be blocked for up to a year on sight. It is considered rude to block such an IP address if it is currently being used by a productive contributor, but it is not against the rules to do so.

IP addresses that are not open-proxies should never be blocked forever, except as described below, because they are frequently shared by many users where the majority are probably legitimate. Temporary blocks of IP addresses should be all that is required to handle a single case of vandalism. Shared IPs (such as those resolving to schools) should only be blocked if there is considerable vandalism that is causing serious disruption to the project. If a block is felt necessary, start with short-term blocks (1 hour, then 2, then 24, etc.), as these often provide sufficient time for the vandal to find other things to do.

Infinite blocks
Beyond open-proxies, infinite blocks should not be employed without good justification. Highly-disruptive vandals, repeat vandals, sockpuppets of known vandals, and usernames with profane words may all be blocked forever without further justification.

Other users who do not fit into the above categories should never be blocked forever. Many disruptive users only need a day or two to "cool off". Many vandals can be blocked for longer periods of time, in the hopes that they reform and come back to be productive, or that they lose interest and never return. Vandals returning from a temporary block to continue vandalizing can be blocked forever.

Block reporting
Blocks, if they require explanation, should be clearly explained by the blocking admin on the user's talk page.

Deleting pages
Pages should only be deleted as per the guidelines on Deletion policy. Speedy delete candidates may be deleted immediately, but other pages may only be deleted as per a consensus discussion on Requests for deletion.

Deleting pages should never be done lightly, and can be a very disruptive action if done incorrectly.

Undeleting pages
Deleted pages may only be undeleted as per a consensus discussion on Requests for undeletion, unless the page was deleted in error. Pages deleted in error may be immediately undeleted by the admin who deleted it. If the deleting admin doesn't undelete it, it must be discussed on Requests for undeletion.

Undeleting pages, especially pages with profanity or pages that contain copyright infringements, may cause bigger problems for the community, and should be carefully considered.

Undeleting pages without justification is a violation of policy.

Protecting pages
Pages may be protected, semi-protected, and unprotected according to the relevant policies. Page protections cannot be altered without proper justification.

Temporary administrators
Temporary administrators are users that are given adminship on a temporary basis. Typically, adminship is granted to perform specialist tasks that only administrators can perform, but would likely be too cumbersome or difficult for permanent administrators to do so.

Temporary administrators must apply at Requests for permissions in the usual fashion, with the following differences:

 * If candidates lack experience on English Wikibooks, experience and trust on other Wikimedia Foundation projects can be highly relevant.
 * Candidates should describe the precise tasks for which they need administrator-only rights, if this is proposed.
 * Following a consensus to promote, adminship should only be granted for the shortest duration needed. Renewals can be requested at WB:RFP.

Users that are global sysops can use their rights pursuant to the global rights policy and hence do not need temporary adminship here. Users that are otherwise eligible to become a global sysop should consider becoming one, though this is not required.

Temporary administrators should only use administrator-only rights for the tasks specified at their request for permissions, unless in an emergency. Since they will have access to the entire administrator abilities, they must take care to avoid using administrator-only rights outside of their stated tasks. The temporary admin may ask any permanent administrator for clarifications on what they are allowed/not allowed to do, and can ask any permanent administrator for permission to amend their conditions if needed (for instance, if they need to do something not originally approved).

Any permanent administrator may request a steward to perform de-adminship immediately if there is any evidence that administrator-only rights are being used outside of the agreed tasks without good reason. If possible this should be discussed with the temporary admin first but in the event that the permanent administrator has reason to believe that the actions are significantly disruptive then they may ask the Steward to act immediately.

Administrators
Temporary administrators are not included in this list. A * indicates that the user is a temporary admin due to MVR, but is not under the policies of a temporary admin

Bureaucrats

 * None at this time

Non-regular administrators
This wiki allows Global sysops and stewards to perform nearly all admin actions here and has opted-in into global sysops

 * Current global sysops can be found at Special:GlobalUsers/global-sysop.

User rights pages
af:Wikibooks:Administrateurs ar:ويكي الكتب:إداريون bg:Уикикниги:Администратори bs:Wikiknjige:Administracija ca:Viquillibres:Administradors cs:Wikiknihy:Správci cy:Wicillyfrau:Gweinyddwyr da:Wikibooks:Administratorer de:Wikibooks:Administratoren es:Wikilibros:Bibliotecarios eo:Vikilibroj:Administrantoj fr:Wikilivres:Administrateur gl:Wikibooks:Administradores ko:위키책:관리자 hr:Wikiknjige:Administratori hy:Վիքիգրքեր:Ադմինիստրատորներ id:Wikibooks:Pengurus is:Wikibækur:Stjórnendur it:Wikibooks:Amministratori ka:ვიკიწიგნები:ადმინისტრატორები he:ויקיספר:מפעיל מערכת la:Vicilibri:Magistratus Segítség/Adminisztrátorok nl:Wikibooks:Moderator ja:Wikibooks:管理者 no:Wikibøker:Administratorer pl:Wikibooks:Administratorzy pt:Wikibooks:Administradores ru:Викиучебник:Администраторы simple:Wikibooks:Administrators sk:Wikibooks:Administrátori fi:Wikikirjasto:Ylläpitäjät sv:Wikibooks:Administratörer th:Wikibooks:ผู้ดูแลระบบ vi:Wikibooks:Bảo quản viên tr:Vikikitap:Yöneticiler zh:Wikibooks:管理员

title: Wikibooks:Administrators


text:
Wikibooks talk:Administrators

Mark admins
I've made User:Minorax/markAdmin.js to indicate the rights functionaries have. Should it be moved to gadget-space so it's more visible? --Minorax (discuss • contribs) 09:21, 20 March 2021 (UTC)
 * for views, I think that seems reasonable. -- Jules (Mrjulesd) 21:16, 20 March 2021 (UTC)
 * What does that script do? Is it just purely cosmetic? Leaderboard (discuss • contribs) 07:28, 21 March 2021 (UTC)
 * Yes, it's cosmetic It'll mark admins with the rights they have. e.g. since QuiteUnusual is a sysop, crat, cu and steward. Their username will appear as QuiteUnusual (A/B/CU/S) . --Minorax (discuss • contribs) 07:36, 21 March 2021 (UTC)
 * I think you can go ahead then, you have interface-admin being a GS and I have no issues with your proposal. Leaderboard (discuss • contribs) 07:38, 21 March 2021 (UTC)
 * Done and gadget seems to be working properly. Minorax (discuss • contribs) 13:30, 21 March 2021 (UTC)
 * , I take it that MediaWiki:Gadget-markAdmins-data.js will have to be kept up-to-date for this to work, right? -- Jules (Mrjulesd) 13:52, 21 March 2021 (UTC)
 * Yes, it'll have to be kept up-to-date. --Minorax (discuss • contribs) 14:19, 21 March 2021 (UTC)

 * Couldnt you just check the userright of the user? I forgot exactly how to do that, but you can use js to check if a user is under certain rights, like sysop and crat. Example at User:L10nM4st3r/ReportUser/Beta.js, although checking if the user is blocked, if you check the output on an admin, you should see the userrights. — L10nM4st3r / ROAR at me! 08:57, 17 October 2023 (UTC)

Right now
right now

41.116.244.252 (discuss) 21:50, 1 October 2023 (UTC)
 * Right now — L10nM4st3r / ROAR at me! 08:51, 17 October 2023 (UTC)

title: Wikibooks talk:Administrators


text: Ancient History/Rome/Mention in Literature


text:
Ancient History/Rome/Romanticism

Romanticism was a secular and intellectual movement in the history of ideas that originated in late 18th century Western Europe. It followed the Enlightenment period and was in part inspired by a revolt against aristocratic social and political norms of the previous period, as well as a reaction against the rationalization of nature by the Enlightenment: Romanticism is an aspect of what has been called the Counter-Enlightenment. It stressed strong emotion (which now might include trepidation, awe, and horror as aesthetic experiences), legitimized the individual imagination as a critical authority (which permitted freedom within or from classical notions of form in art), and overturned some previous social conventions. There was a strong recourse to historical and natural inevitability in the representation of its ideas.

Romanticism stressed the awe of "nature" in art and language and the experience of sublimity through a connection with nature. An influence upon the Romantic movement by the ideologies and events of the French Revolution is thought to have characterized the movement. Romanticism is also noted for its elevation of the achievements of what it perceived as misunderstood heroic individuals and artists that altered society altogether.

title: Ancient History/Rome/Romanticism


text:
Purported Ancient Worlds/Atlantis

Atlantis is an ancient mythical island, whose existence and location have never been confirmed. The first known references to Atlantis are from the classical Greek philosopher Plato, who said it was engulfed by the ocean as the result of an earthquake 9,000 years before his own time. Plato claimed it was somewhere outside the Pillars of Hercules, now known as the Strait of Gibraltar. While there are many theories about Atlantis, nearly all serious research concludes that Atlantis never existed as Plato described it, although elements of his story may have been drawn from real events.

title: Purported Ancient Worlds/Atlantis


text:
Wikibooks:Copyrights/Proposed merger

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title: Wikibooks:Copyrights/Proposed merger


text:
User:B7T

Hello. I don't have any contributions here yet. If you'd like to know a little more about me, you can see my user page at Wikipedia.

title: User:B7T


text:
QBasic/Full Book View

= Basic Input =

= Text Output =

= Basic Math =

= Flow Control =

= Advanced Input =

= Subroutines and Functions =

= Arrays and Types =

= Files =

= Advanced Text Output =

= Sound =

= Graphics =

= Advanced Graphics =

= 3d Graphics =

= Images =

= What Next =

= Sample Programs =

= Appendix =

= Authors =

title: QBasic/Full Book View


text:
Communication Systems/Noise Figure

This page is going to talk about the effect of noise on transmission systems.

Types of Noise
Most man made electro-magnetic noise occurs at frequencies below 500 MHz. The most significant of these include:

 * • Hydro lines
 * • Ignition systems
 * • Fluorescent lights
 * • Electric motors

Therefore deep space networks are placed out in the desert, far from these sources of interference.

There are also a wide range of natural noise sources which cannot be so easily avoided, namely:

 * •Atmospheric noise - lighting < 20 MHz
 * •Solar noise - sun - 11 year sunspot cycle
 * •Cosmic noise - 8 MHz to 1.5 GHz
 * •Thermal or Johnson noise. Due to free electrons striking vibrating ions.
 * •White noise - white noise has a constant spectral density over a specified range of frequencies. Johnson noise is an example of white noise.
 * •Gaussian noise - Gaussian noise is completely random in nature however, the probability of any particular amplitude value follows the normal distribution curve. Johnson noise is Gaussian in nature.
 * •Shot noise - bipolar transistors
 * $$i_n = \sqrt {2qI_{dc} \Delta f} $$
 * where q = electron charge 1.6 x 10-19 coulombs
 * •Excess noise, flicker, 1/f, and pink noise < 1 KHz are Inversely proportional to frequency and directly proportional to temperature and dc current
 * •Transit time noise - occurs when the electron transit time across a junction is the same period as the signal.

Of these, only Johnson noise can be readily analysed and compensated for. The noise power is given by:

 * $$P_n = kTB$$

Where:

 * k = Boltzmann's constant (1.38 x 10-23 J/K)
 * T = temperature in degrees Kelvin
 * B = bandwidth in Hz

This equation applies to copper wire wound resistors, but is close enough to be used for all resistors. Maximum power transfer occurs when the source and load impedance are equal.

Combining Noise Voltages
The instantaneous value of two noise voltages is simply the sum of their individual values at the same instant.

 * $$v_{total\;inst} = v_{1\;inst}  + v_{2\;inst} $$

This result is readily observable on an oscilloscope. However, it is not particularly helpful, since it does not result in a single stable numerical value such as one measured by a voltmeter.

If the two voltages are coherent [K = 1], then the total rms voltage value is the sum of the individual rms voltage values.

 * $$v_{total\;rms} = v_{1\;rms}  + v_{2\;rms} $$

If the two signals are completely random with respect to each other [K = 0], such as Johnson noise sources, the total power is the sum of all of the individual powers:

 * $$P_{total\;random\;noise} = P_{n1\;random}  + P_{n2\;random} $$

A Johnson noise of power P = kTB, can be thought of as a noise voltage applied through a resistor, Thevenin equivalent.

 * [[Image:noise source.gif]]

An example of such a noise source may be a cable or transmission line. The amount of noise power transferred from the source to a load, such as an amplifier input, is a function of the source and load impedances.

 * [[Image:noise circuit.gif]]

If the load impedance is 0 $$\Omega$$, no power is transferred to it since the voltage is zero. If the load has infinite input impedance, again no power is transferred to it since there is no current. Maximum power transfer occurs when the source and load impedances are equal.

 * $$P_{L\;\max } = \frac$$

The rms noise voltage at maximum power transfer is:

 * $$e_n = \sqrt {4RP}  = \sqrt {4RkTB} $$

 * [[Image:matched thermal noise.gif]]

Observe what happens if the noise resistance is resolved into two components:

 * $$e_n^2 = 4RkTB = 4\left( {R_1  + R_2 } \right)kTB = e_{n1}^2  + e_{n2}^2 $$

From this we observe that random noise resistance can be added directly, but random noise voltages add vectorially:

 * [[Image:vector addition.gif]]

If the noise sources are not quite random, and there is some correlation between them [0 < K < 1], the combined result is not so easy to calculate:

 * $$P_{Total\;\left( {{\rm{not }}\;{\rm{quite}}\;{\rm{ random}}} \right)} = \frac = P_1  + P_2  = 2K\sqrt {P_1  + P_2 } $$

 * where

 * K = correlation [0 < K < 1]
 * R0 = reference impedance

Noise Temperature
The amount of noise in a given transmission medium can be equated to thermal noise. Thermal noise is well-studied, so it makes good sense to reuse the same equations when possible. To this end, we can say that any amount of radiated noise can be approximated by thermal noise with a given effective temperature. Effective temperature is measured in Kelvin. Effective temperature is frequently compared to the standard temperature, $$T_o$$, which is 290 Kelvin.

In microwave applications, it is difficult to speak in terms of currents and voltages since the signals are more aptly described by field equations. Therefore, temperature is used to characterize noise. The total noise temperature is equal to the sum of all the individual noise temperatures.

Noise Figure
The terms used to quantify noise can be somewhat confusing but the key definitions are:

 * Signal to noise ratio: It is either unitless or specified in dB. The S/N ratio may be specified anywhere within a system.

 * $$\frac{S}{N} = \frac = \frac$$

 * $$\left( {\frac{S}{N}} \right)_{dB} = 10\log \frac$$

 * Noise Factor (or Noise Ratio): $$F = \frac$$ (unit less)

 * Noise Figure: $$NF = 10\log F = SNR_{in} - SNR_{out} $$ dB

This parameter is specified in all high performance amplifiers and is measure of how much noise the amplifier itself contributes to the total noise. In a perfect amplifier or system, NF = 0 dB. This discussion does not take into account any noise reduction techniques such as filtering or dynamic emphasis.

 * [[Image:g.gif]]

Friiss' Formula & Amplifier Cascades
It is interesting to examine an amplifier cascade to see how noise builds up in a large communication system.

 * $$F = \frac = \frac \times \frac$$

Amplifier gain can be defined as: $$G = \frac$$

 * [[Image:g2.gif]]

 * Therefore the output signal power is: $$S_{out} = GS_{in}$$

 * and the noise factor (ratio) can be rewritten as: $$F = \frac \times \frac = \frac$$

 * The output noise power can now be written: $$N_{out} = FGN_{in} $$

From this we observe that the input noise is increased by the noise ratio and amplifier gain as it passes through the amplifier. A noiseless amplifier would have a noise ratio (factor) of 1 or noise figure of 0 dB. In this case, the input noise would only be amplified by the gain since the amplifier would not contribute noise.

 * The minimum noise that can enter any system is the Johnson Noise:

 * $$N_{in\left( \right)}  = kTB$$

 * Therefore the minimum noise that can appear at the output of any amplifier is:

 * $$N_{out\left( \right)}  = FGkTB$$

 * The output noise of a perfect amplifier would be (F = 1):

 * $$N_{out\left( \right)}  = GkTB$$

 * The difference between these two values is the noised created (added) by the amplifier itself:

 * $$N_{out\left( \right)}  = N_{out\left(  \right)}  - N_{out\left(  \right)}  = FGkTB - GkTB = \left( {F - 1} \right)GkTB$$

 * This is the additional (created) noise, appearing at the output.

The total noise out of the amplifier is then given by:

 * $$N_{total} = N_{out\left(  \right)}  + N_{out\left(  \right)}  = GkTB + \left( {F - 1} \right)GkTB$$

If a second amplifier were added in series, the total output noise would consist the first stage noise amplified by the second stage gain, plus the additional noise of the second amplifier:

 * $$N_{total} = G_1 G_2 kTB + \left( {F_1  - 1} \right)G_1 G_2 kTB + \left( {F_2  - 1} \right)G_2 kTB$$

 * If we divide both sides of this expression by the common term: $$G_1 G_2 kTB$$

 * we obtain:

 * $$\frac = \frac$$

 * Recall: $$F = \frac = \frac$$

 * Then: $$F_{overall} = F_1  + \frac$$

This process can be extended to include more amplifiers in cascade to arrive at:

 * Friiss' Formula

 * $$F = F_1 + \frac + \frac +   $$

This equation shows that the overall system noise figure is largely determined by the noise figure of the first stage in a cascade since the noise contribution of any stage is divided by the gains of the preceding stages. This is why the 1st stage in any communication system should be an LNA (low noise amplifier).

Receiver Sensitivity
In a given bandwidth, W, we can show that the noise power N equals:

 * $$N = F(kT_0)W$$

From N, we can show that the sensitivity of the receiver is equal to

 * $$SNR \times N$$

title: Communication Systems/Noise Figure


text:
QBasic/Basic Math

There are six numerical variables within QBasic:

Please note that Integer and Float type variables for 64-bit are available only in QB64.

A lot of programming is math. Don't let this scare you: a lot of the math is simple, but it's still math. In this section, we will look at doing some basic math (the same stuff you learned in the 3rd grade) and manipulating numbers.

Equation Setup
In QBasic an equation has a basic setup a right side and a left side. For instance X=5, as you can probably figure out, this sets the variable X to 5. But we can use variables on the right side too. Y=X*10 would set Y equal to 10 times X, in this situation, 50. In this next program I will show several equations to give you a feel for math.

Understanding 7MATH.BAS
The most important thing you can take away from this is the setup for math equations. I think you can figure out what all the symbols are and what they do, but QBasic is picky about equations. For 'e=a+b', if you try 'a+b=e' it will not work. The final thing I would like to address in 7MATH.BAS is the INT function. As far as vocabulary, a function is something that takes in a piece of information and gives you another piece of information back. So PRINT, was a statement, and INT is a function. The INT function takes a number and truncates its decimal, it does not round. So INT(5.1) is 5 and INT(5.999) is still 5. If you want to round a number use CINT.

Understanding 8MATH.BAS
8MATH.BAS shows one simple concept that is very important in programming, but impossible in math. The way that the computer calculates the equation is it does all the math on the right side of the equation and then sticks it in the variable on the left side. So the equation x=x+5 makes perfect sense, unlike math where it is a contradiction. Reassigning a value to a variable based on its current value is common and a good way to keep the number of variables down.

Tip Calculator
9TIP.BAS calculates your tip and total bill from the bill and percent tip you wish to give. The first three lines clear the screen and get the information from the user. The fifth line changes the tip from a percent to the correct decimal by dividing by 100 (ex. 20%=.2 because 20/100=.2) the next line takes that percent and turns it into a dollar value by multiplying the decimal value by the bill. So if your bill is $20.00 and you leave a 20% tip, it multiplies 20*.2 which is 4 or $4.00. The last three lines format the output. This is a good example of a complete program. It collects information from the user, it processes the information and it gives the user feedback. Also, the middle section of the program is a good example of variable conservation. This is subject that will take some practice to get used to. In writing a program, if you use too many variables, it will become difficult to keep track of all of them. If you try and conserve too much, you code may become difficult to understand.

You may notice that the program may print more than two decimal places if you enter a bill that is not an exact dollar value. As an exercise, try modifying the program so that it only displays two decimal places - you can use the  function or any other rounding method you intend to use.

Parentheses and Order of Operations
10OROP.BAS is an example of order of operations and how parentheses can be used to manipulate it. I do not want to go into an indepth explanation of the order of operations here. The best advice I can give is unless you are sure of the order of operations, use parentheses to make sure the equation works how you want. All you need to know about parentheses is that the deepest nested parentheses calculate first. If you wish to know more, there are plenty of algebra resources available. On that note, you may wish to brush up on algebra. While it is not necessary for programming, it can help make programming easier and it can allow you to create more advanced programs.

Random Numbers
Though we will not go into their use until the next section, I would like to discuss the generation of random numbers. QBasic has a random number statement, RND, that generates a random decimal between 0 and 1. You can think of it as a random percent. At first, this may seem like an odd way to generate random numbers. However, with a little math it is very easy to manipulate this to provide numbers in whatever range you want. The first step is to multiply RND by a number (the range you want). For instance 'RND*10'. This will return random numbers (decimal numbers) between 0 and 10(both included). So, to pick a random number between zero and ten we would say '(RND*10)'

More on RND
A few notes on 11RND.BAS, the second line, RANDOMIZE TIMER, sets it so that the computer uses the current time to pick random number. If you don't do this, it picks the same random number every time (try it, write a one line program, PRINT RND, and run it over and over, your screen will fill up with the same number) this can prove useful for some applications, but not most. Stick RANDOMIZE TIMER in at the top of all your programs that use the RND statement and they will be far less predictable. This program just show some ways to choose what you want from your random number generator. The last line shows that you can be very specific in what you get. Make sure to run this program several times to see the different results.

title: QBasic/Basic Math


text:
Communication Systems/Space-Division Multiplexing

This page is all about Space-Division Multiplexing (SDM).

 * What is SDM: When we want to transmit multiple messages, the goal is maximum reuse of the given resources: time and frequency. Time-Division Multiplexing (TDM), operates by dividing the time up into time slices, so that the available time can be reused. Frequency-Division Multiplexing (FDM), operates by dividing up the frequency into transmission bands, so that the frequency spectrum can be reused. However, if we remember our work with directional antennas, we can actually reuse both time and frequency, by transmitting our information along parallel channels. This is known as Space-Division Multiplexing.


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Cookbook talk:Chocolate Fudge

Hi - This recipe doesn't seem to be for [plain] chocolate fudge, as it involves marshmallow cream (which isn't actually available outside of the US). Traditional fudge is just made from milk and chocolate and stuff. Perhaps it could be renamed Marshmallow fudge? Also, does anyone have a good recipe for plain chocolate fudge? - Jb 21:35, 8 May 2006 (UTC)

dude, hate to say this but all fudge has mashmellow in it.--24.19.228.205 (talk) 00:21, 23 February 2009 (UTC)

title: Cookbook talk:Chocolate Fudge


text:
Talk:X86 assembly

Here is the original text of this page. --Whiteknight (talk)(projects) 00:16, 9 May 2006 (UTC)

Assembly for beginners
This book takes the opposite approach to teaching assembly by assuming the reader doesn't know anything about programming. It tries to make it as easy as possible to learn x86 assembly. To be useful to as many people as possible, this tutorial will assume that you're running Windows (2000 or higher.)

x86 means:
x86 is a family of 32-bit processors which includes the 386, 486, Pentium (586), Pentium Pro (686), Pentium 2, 3, 4, as well as all AMD processors such as the Duron and Athlon XP. This tutorial assumes that you have a 586 or higher processor.

Binary and hex
When programming assembly, binary and hexadecimal numbers are often used in place of their base 10 counterparts. There are many other pages on the web which cover this subject in great detail.

Hands on experiment
Go to start>run and type cmd.exe

This will send you into the windows command prompt, from here type debug and press enter then type r and press enter.

For now let's just explain what the lines a-dx=0000 mean, these are general purpose registers, and note that the 0000 is hexadicimal, not decimal or binary.

(place holder)

type a then enter

type mov ax,100 then enter twice

type t

you will notice that AX=0000 has now changed to AX=0100, not a whole lot of interesting stuff going on there. the mov instruction moves the second value into the first thing you give it. try this

a

mov bx,ax (enter twice)

t

note that bx now has the same value as ax, the value of ax was moved or copied into bx.

the commands add and sub work about the same and you can imagine what they do. You might be wondering what happens when you add 1 to FFFF, go ahead and try it just goes to zero, 2+FFFF=1, etc. same for subtracting.

mov ax,FFFF

add ax,1

-t

AX=0000

Also the registers can be split by changing the "x" in ax,bx,etc... to l or h, you can enter a two digit hexadecimal number, h is two high digits, l is two low digits. h would go on the left, l on the right.

mov ah,FF

add ah,2

t

AX=0100

note that only the first two decimals were changed.

To go any further
Well I don't really know how to do much more of this and you may have notice that the windows command line doesn't work so well and doesn't always give you what you think the answer should be. since all tutorials are outdated and windows is said to be horible for assembly programming someone needs to contribute a a better tutorial with an instruction on how to set up an emulation of a good operating system for assembly.

title: Talk:X86 assembly