Un livre de Wikibooks.

Sections 1 Installation de logiciels 1.1 Installation de Python 1.1.1 Sous Windows 1.1.2 Sous Linux 1.1.3 Sous MacOS 1.2 Installation de SciTE (Scintilla Text Editor) 1.2.1 Installation sous Linux : 1.2.2 Installation sous Windows : 1.2.3 Pour les deux versions 1.3 Installation des Python méga-widgets 1.4 Installation de Gadfly (système de bases de données) 1.4.1 Sous Windows  : 1.4.2 Sous Linux : 2 Annexes extraites de « How to think like a computer scientist » 2.1 Contributor list 2.2 Preface 3 GNU Free Documentation License 3.1 Preamble 3.2 Applicability and Definitions 3.3 Verbatim Copying 3.4 Copying in Quantity 3.5 Modifications 3.6 Combining Documents 3.7 Collections of Documents 3.8 Translation 3.9 Termination 3.10 Future Revisions of This License

[modifier] Installation de logiciels

[modifier] Installation de Python

Si vous souhaitez essayer Python sur votre ordinateur personnel, n'hésitez pas : l'installation est très facile (et parfaitement réversible).

[modifier] Sous Windows

Sur le site web officiel de Python : http://www.python.org, vous trouverez dans la section « Download » des logiciels d'installation automatique pour les différentes versions de Python. Vous pouvez en confiance choisir la dernière version « de production ».

Par exemple, au 30/9/03, il s'agit de la version 2.3.1 - Fichier à télécharger : Python-2.3.1.exe

Copiez ce fichier dans un répertoire temporaire de votre machine, et exécutez-le. Python s'installera par défaut dans un répertoire nommé « Python** » (** indiquant les deux premiers chiffres du n° de version), et des icônes de lancement seront mises en place automatiquement.

Lorsque l'installation est terminée, vous pouvez effacer le contenu du répertoire temporaire.

[modifier] Sous Linux

Vous avez probablement installé votre système Linux à l'aide d'une distribution commerciale telle que SuSE, RedHat ou Mandrake. Installez simplement les paquetages Python qui en font partie, en n'omettant pas Tkinter (parfois installé en même temps que la Python imaging library).

[modifier] Sous MacOS

Vous trouverez différentes versions de Python pour MacOS 9 et Mac OS X sur le site web de Jack Jansen : http://homepages.cwi.nl/~jack/macpython.

[modifier] Installation de SciTE (Scintilla Text Editor)

SciTE est un excellent logiciel éditeur, capable d'effectuer la coloration syntaxique, l'auto-complétion et surtout le repliement de code (code folding), c'est à dire le masquage à volonté de différents blocs d'instructions (contenu d'une classe, d'une fonction, d'une boucle, etc.) : cette fonctionnalité se révèle extrêmement pratique lorsque vos scripts commencent à s'allonger ... Il intègre également une fenêtre de terminal ainsi qu'un raccourci pour lancement des scripts.

Cet éditeur est disponible pour Windows et pour Linux. Veuillez consulter le site web : http://www.scintilla.org/SciTE.html.

[modifier] Installation sous Linux :

L'éditeur Scintilla fait dorénavant partie des paquetages fournis d'office avec les distributions récentes de Linux. Sinon, téléchargez-le au départ du site web mentionné ci-dessus. Sinon :

• téléchargez l'archive gscite***.tgz puis l'extraire avec tar ;

• installez l'exécutable SciTE dans /usr/local/bin ;

• installez tout le reste (fichiers *.properties) dans /usr/share/scite (et non /usr/share/gscite !).

[modifier] Installation sous Windows :

• Téléchargez l'archive wscite***.zip puis l'extraire dans \Program files ;

• installez une icône de lancement pour l'exécutable SciTe.exe.

[modifier] Pour les deux versions

On peut personnaliser beaucoup de choses (polices, etc.) en éditant le fichier des propriétés globales (Menu Options → Open global options file).

Par exemple, pour activer de jolis symboles pour replier/déplier, dans la marge de gauche :

• fold.symbols = 2 # pour de belles icônes + et - cerclées
• fold.on.open = 1 # ainsi tout est plié au départ
• margin.width =0 # pour supprimer la marge inutile

Pour forcer le remplacement automatique des tabulations par des groupes de 4 espaces :

• tabsize = 4
• indent.size = 4
• use.tabs = 0

[modifier] Installation des Python méga-widgets

Visitez le site web : http://pmw.sourceforge.net et cliquez sur le lien : « Download Pmw12tar.gz » pour télécharger le fichier correspondant.

Décomprimez ce fichier archive dans un répertoire temporaire, à l'aide d'un logiciel de décompression tel que tar, Winzip, Info-Zip, unzip…

Recopiez l'intégralité du sous-répertoire Pmw qui s'est créé automatiquement, dans le répertoire où se trouve déjà l'essentiel de votre installation de Python.

Sous Windows, il s'agira par exemple de C:\Python23.

Sous Linux, il s'agira vraisemblablement de /usr/lib/python.

[modifier] Installation de Gadfly (système de bases de données)

Depuis le site http://sourceforge.net/projects/gadfly, télécharger le paquetage gadfly-1.0.0.tar.gz. Il s'agit d'un fichier archive comprimé. Copiez ce fichier dans un répertoire temporaire.

[modifier] Sous Windows  :

Dans un répertoire temporaire quelconque, décomprimez le fichier archive à l'aide d'un logiciel tel que Winzip.

Ouvrez une fenêtre DOS et entrez dans le sous-répertoire qui s'est créé automatiquement.

Lancez la commande : python setup.py install

C'est tout. Vous pouvez éventuellement améliorer les performances, en ajoutant l'opération suivante :

Dans le sous-répertoire qui s'est créé, ouvrez le sous-répertoire kjbuckets, puis le sous-répertoire qui correspond à votre version de Python. Recopiez le fichier *.pyd qui s'y trouve dans le répertoire racine de votre installation de Python.

Lorsque tout est terminé, effacez le contenu de votre répertoire temporaire.

[modifier] Sous Linux :

En tant qu'administrateur (root), choisissez un répertoire temporaire quelconque et décomprimez-y le fichier archive à l'aide de l'utilitaire tar, qui fait certainement partie de votre distribution. Entrez simplement la commande : tar -xvzf gadfly-1.0.0.tar.gz

Entrez dans le sous-répertoire qui s'est créé automatiquement : cd gadfly-1.0.0

Lancez la commande : python setup.py install

C'est tout. Si votre système Linux comporte un compilateur C, vous pouvez améliorer les performances de Gadfly en recompilant la bibliothèque kjbuckets. Pour ce faire, entrez encore les deux commandes suivantes :

• cd kjbuckets
• python setup.py install

Lorsque tout est terminé, effacez tout le contenu du répertoire temporaire.

[modifier] Annexes extraites de « How to think like a computer scientist »

Suivant les termes de la GNU Free Documentation licence (voir p. 366), les annexes qui suivent doivent obligatoirement accompagner telles quelles toute distribution du texte original, que celui-ci ait été modifié (traduit, par exemple) ou non.

[modifier] Contributor list

by Jeffrey Elkner

Perhaps the most exciting thing about a free content textbook is the possibility it creates for those using the book to collaborate in its development. I have been delighted by the many responses, suggestions, corrections, and words of encouragement I have received from people who have found this book to be useful, and who have taken the time to let me know about it.

Unfortunately, as a busy high school teacher who is working on this project in my spare time (what little there is of it ;-), I have been neglectful in giving credit to those who have helped with the book. I always planned to add an "Acknowlegdements" sections upon completion of the first stable version of the book, but as time went on it became increasingly difficult to even track those who had contributed.

Upon seeing the most recent version of Tony Kuphaldt's wonderful free text, "Lessons in Electric Circuits", I got the idea from him to create an ongoing "Contributor List" page which could be easily modified to include contributors as they come in.

My only regret is that many earlier contributors might be left out. I will begin as soon as possible to go back through old emails to search out the many wonderful folks who have helped me in this endeavour. In the mean time, if you find yourself missing from this list, please accept my humble apologies and drop me an email at jeff@elkner.net to let me know about my oversight.

And so, without further delay, here is a listing of the contributors:

• Lloyd Hugh Allen, Lloyd sent in a correction to section 8.4. He can be reached at: lha2@columbia.edu
• Yvon Boulianne, Yvon sent in a correction of a logical error in Chapter 5. She can be reached at: mystic@monuniverse.net
• Fred Bremmer, Fred submitted a correction in section 2.1. He can be reached at: Fred.Bremmer@ubc.cu
• Jonah Cohen, Jonah wrote the Perl scripts to convert the LaTeX source for this book into beautiful HTML. His Web page is jonah.ticalc.org and his email is JonahCohen@aol.com
• Michael Conlon, Michael sent in a grammer correction in Chapter 2 and an improvement in style in Chapter 1, and he initiated discussion on the technical aspects of interpreters. Michael can be reached at: michael.conlon@sru.edu
• Courtney Gleason, Courtney and Katherine Smith created the first version of horsebet.py, which is used as the case study for the last chapters of the book. Courtney can be reached at: orion1558@aol.com
• Lee Harr, Lee submitted corrections for sections 10.1 and 11.5. He can be reached at: missive@linuxfreemail.com
• James Kaylin, James is a student using the text. He has submitted numerous corrections. James can be reached by email at: Jamarf@aol.com
• David Kershaw, David fixed the broken catTwice function in section 3.10. He can be reached at: david_kershaw@merck.com
• Eddie Lam, Eddie has sent in numerous corrections to Chapters 1, 2, and 3. He also fixed the Makefile so that it creates an index the first time it is run and helped us set up a versioning scheme. Eddie can be reached at: nautilus@yoyo.cc.monash.edu.au
• Man-Yong Lee, Man-Yong sent in a correction to the example code in section 2.4. He can be reaced at: yong@linuxkorea.co.kr
• David Mayo, While he didn't mean to hit us over the head with it, David Mayo pointed out that the word "unconsciously" in chapter 1 needed to be changed to "subconsciously". David can be reached at: bdbear44@netscape.net
• Chris McAloon, Chris sent in several corrections to sections 3.9 and 3.10. He can be reached at: cmcaloon@ou.edu
• Matthew J. Moelter, Matthew has been a long-time contributor who sent in numerous corrections and suggestions to the book. He can be reached at: mmoelter@calpoly.edu
• Simon Dicon Montford, Simon reported a missing function definition and several typos in Chapter 3. He also found errors in the increment function in Chapter 13. He can be reached at: dicon@bigfoot.com
• John Ouzts, John sent in a correction to the "return value" definition in Chapter 3. He can be reached at: jouzts@bigfoot.com
• Kevin Parks, Kevin sent in valuable comments and suggestions as to how to improve the distribution of the book. He can be reached at: cpsoct@lycos.com
• David Pool, David sent in a typo in the glossary of chapter 1, as well as kind words of encouragement. He can be reached at: pooldavid@hotmail.com
• Michael Schmitt, Michael sent in a correction to the chapter on files and exceptions. He can be reached at: ipv6_128@yahoo.com
• Paul Sleigh, Paul found an error in Chapter 7 and a bug in Jonah Cohen's Perl script that generates HTML from LaTeX. He can be reached at: bat@atdot.dotat.org
• Christopher Smith, Chris is a computer science teacher at the Blake School in Minnesota who teaches Python to his beginning students. He can be reached at: csmith@blakeschool.org or smiles@saysomething.com
• Katherine Smith, Katherine and Courtney Gleason created the first version of horsebet.py, which is used as the case study for the last chapters of the book. Katherine can be reached at: kss_0326@yahoo.com
• Craig T. Snydal, Craig is testing the text in a course at Drew University. He has contributed several valuable suggestions and corrections, and can be reached at: csnydal@drew.edu
• Ian Thomas, Ian and his students are using the text in a programming course. They are the first ones to test the chapters in the latter half of the book, and they have make numerous corrections and suggestions. Ian can be reached at: ithomas@sd70.bc.ca
• Keith Verheyden , Keith made correction in Section 3.11 and can be reached at: kverheyd@glam.ac.uk
• Chris Wrobel, Chris made corrections to the code in the chapter on file I/O and exceptions. He can be reached at: ferz980@yahoo.com
• Moshe Zadka, Moshe has made invaluable contributions to this project. In addition to writing the first draft of the chapter on Dictionaries, he provided continual guidance in the early stages of the book. He can be reached at: moshez@math.huji.ac.il

[modifier] Preface

by J. Elkner

This book owes its existance to the collaboration made possible by the internet and the free software movement. Its three authors, a college professor, a high school teacher, and a professional programmer, have yet to meet face to face, but we have been able to work closely together, and have been aided by many wonderful folks who have donated their time and energy to helping make it better.

What excites me most about it is that it is a testament to both the benefits and future possibilities of this kind of collaboration, the framework for which has been put in place by Richard Stallman and the Free Software Foundation.

a)How and why I came to use Python

In 1999, the College Board's Advanced Placement Computer Science exam was given in C++ for the first time. As in many high schools throughout the country, the decision to change languages had a direct impact on the computer science curriculum where I teach at Yorktown High School, in Arlington, Virginia. Up to this point, Pascal was the language of instruction in both our first year and AP courses. In keeping with past practice of giving students two years of exposure to the same language, we made the decision to switch to C++ in the first year course for the 1997-98 school year, so that we would be in step with the College Board's change for the AP course the following year.

Two years later, I was convinced that C++ was a poor choice to use for introducing students to computer science. While it is certainly a very powerful programming language, it is also an extremely difficult language to learn and teach. I found myself constantly fighting with C++'s difficult syntax and multiple ways of doing things, and I was losing many students unnecessarily as a result. Convinced there had to be a better language choice for our first year class, I went looking for an alternative to C++.

A discussion on the High School Linux Users' Group mailing list provided a solution. A thread emerged during the latter part of January, 1999 concerning the best programming language for use with first time high school computer science students. In a posting on January 30th, Brendon Ranking wrote:

« I believe that Python is the best choice for any entry-level programming class. It teaches proper programming principles while being incredibly easy to learn. It is also designed to be object oriented from its inception so it doesn't have the add-on pain that both Perl and C++ suffer from...... It is also *very* widely supported and very much web-centric, as well. »

I had first heard of Python a few years earlier at a Linux Install Fest, when an enthusiastic Michael McLay told me about Python's many merits. He and Brendon had now convinced me that I needed to look into Python.

Matt Ahrens, one of Yorktown's gifted students, jumped at the chance to try out Python, and in the final two months of the 1998-99 school year he not only learned the language but wrote an application called pyTicket which enabled our staff to report technology problems via the web. I knew that Matt could not have finished an application of that scale in so short a time in C++, and this accomplishment combined with Matt's positive assessment of Python suggested Python was the solution I was looking for.

b)Finding a text book

Having decided to use Python in both my introductory computer science classes the following year, the most pressing problem was the lack of an available text book.

Free content came to the rescue. Earlier in the year Richard Stallman had introduced me to Allen Downey. Both of us had written to Richard expressing an interest in developing free educational content. Allen had already written a first year computer science text book titled, How to think like a computer scientist. When I read this book I knew immediately that I wanted to use it in my class. It was the clearest and most helpful computer science text I had seen. It emphasized the processes of thought involved in programming, rather than the features of a particular language. Reading it immediately made me a better teacher.

Not only was How to think like a computer scientist an excellent book, but it was also released under a GNU public license, which meant it could be used freely and modified to meet the needs of its user. Once I decided to use Python, it occurred to me that I could translate Allen's original Java version into the new language. While I would not have been able to write a text book on my own, having Allen's book to work from made it possible for me to do so, at the same time demonstrating that the cooperative development model used so well in software could also work for educational content.

Working on this book for the last two years has been rewarding for both me and my students, and the students played a big part in the process. Since I could make instant changes whenever someone found a spelling error or difficult passage, I encouraged them to look for errors in the book by giving them a bonus point every time they found or suggested something that resulted in a change in the text. This had the double benefit of encouraging them to read the text more carefully, and of getting the text thoroughly reviewed by its most important critics, students using it to learn computer science.

For the second half of the book on object oriented programming, I knew that someone with more real programming experience than I had would be needed to do it right. The book actually sat in an unfinished state for the better part of a year until two things happened that led to its completion.

I received an email from Chris Meyers expressing interest in the book. Chris is a professional programmer who started teaching a programming course last year using Python at Lane Community College in Eugene Oregon. The prospect of teaching the course had led Chris to the book, and he started helping out with it immediately. By the end of the school year he had created a companion project on our web site at http://www.ibiblio.org/obp called Python for Fun and was working with some of my most advanced students as a master teacher, guiding them beyond the places I could take them.

c)Introducing programming with Python

The process of translating and using How to think like a computer scientist for the past two years has confirmed Python's suitability to teaching beginning students. Python greatly simplifies programming examples and makes important programming ideas easier to teach.

The first example from the text dramatically illustrates this point. It is the traditional "hello, world" program, which in the C++ version of the book looks like this:

	#include <iostream.h>
	void main()
	{
    		cout << "Hello, world." << endl;
	}

in the Python version it becomes:

	print "Hello, World!"

Even though this is a trivial example, the advantages to Python stand out. There are no prerequisites to Yorktown's Computer Science I course, so many of the students seeing this example are looking at their first program. Some of them are undoubtedly a little nervous, having heard that computer programming is difficult to learn. The C++ version has always forced me to choose between two unsatisfying options: either to explain the #include, void main(), {, and } statements, and risk confusing or intimidating some of the students right at the start, or to tell them "just don't worry about all of that stuff now, we will talk about it later" and risk the same thing. The educational objectives at this point in the course are to introduce students to the idea of a programming statement and to get them to make their first program, thereby introducing them to the programming environment. The Python program has exactly what is needed to do these things, and nothing more.

Comparing Section 1.5 of each version of the book, where this first program is located, further illustrates what this means to the beginning student. There are thirteen paragraphs of explanation of "Hello, world" in the C++ version, in the Python version there are only two. More importantly, the missing eleven paragraphs do not deal with the "big ideas" in computer programming, but with the minutia of C++ syntax. I found this same thing happening throughout the book. Whole paragraphs simply disappear from the Python version of the text because Python's much clearer syntax renders them unnecessary.

Using a very high level language like Python allows a teacher to postpone talking about low level details of the machine until students have the background that they need to better make sense of the details. It thus creates the ability to put "first things first" pedagogically.

One of the best examples of this is the way in which Python handles variables. In C++ a variable is a name for a place which holds a thing. Variables have to be declared with types at least in part because the size of the place to which they refer needs to be predetermined. Thus the idea of a variable is bound up with the hardware of the machine. The powerful and fundamental concept of a variable is already difficult enough for beginning students (in both Computer Science and Algebra). Bytes and addresses do not help the matter. In Python a variable is a name which refers to a thing. This is a far more intuitive concept for beginning students, and one which is much closer to the meaning of variable that they learned in their math class. I had much less difficulty teaching variables this year than I did in the past, and I spent less time helping students with problems using them.

Another example of how Python aides in the teaching and learning of programming is in its syntax for functions. My students have always had a great deal of difficulty understanding functions. The main problem centers around the difference between a function definition and a function call, and the related distinction between a parameter and an argument. Python comes to the rescue with syntax that is nothing short of beautiful. Function definitions begin with the key word def, so I simply tell my students, "when you define a function, begin with def, followed by the name of the function that you are defining, when you call a function, simply call (type) out its name." Parameters go with definitions, arguments go with calls. There are no return types or parameter types or reference and value parameters to get in the way, so I am now able to teach functions in less then half the time that it previously took me, with better comprehension.

Using Python has improved the effectiveness of our computer science program for all students. I see a higher general level of success and a lower level of frustration than I experienced during the two years using C++. I move faster with better results. More students leave the course with the ability to create meaningful programs, and with the positive attitude toward the experience of programming that this engenders.

d)Building a community

I have received email every continent on the globe and from as far away as Korea from people using this book to learn or to teach programming. A user community has begun to emerge and increasing numbers of people have been contributing to the project by sending in materials for the companion web site at http://www.ibiblio.org/obp.

With the publication of the book in print form, I expect the growth in the user community to continue and accelerate. It is the emergence of this user community and the possibility it suggests for similar collaboration among educators that has been the most exciting thing for me about working on the project. By working together we can both increase the quality of materials available for our use and save valuable time. I invite you to join our community and look forward to hearing from you.

Jeffrey Elkner
Yorktown High School
Arlington, Virginia

[modifier] GNU Free Documentation License

Version 1.1, March 2000 Copyright © 2000 Free Software Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.

[modifier] Preamble

The purpose of this License is to make a manual, textbook, or other written document "free" in the sense of freedom: to assure everyone the effective freedom to copy and redistribute it, with or without modifying it, either commercially or noncommercially. Secondarily, this License preserves for the author and publisher a way to get credit for their work, while not being considered responsible for modifications made by others.

This License is a kind of "copyleft," which means that derivative works of the document must themselves be free in the same sense. It complements the GNU General Public License, which is a copyleft license designed for free software.

We have designed this License in order to use it for manuals for free software, because free software needs free documentation: a free program should come with manuals providing the same freedoms that the software does. But this License is not limited to software manuals; it can be used for any textual work, regardless of subject matter or whether it is published as a printed book. We recommend this License principally for works whose purpose is instruction or reference.

[modifier] Applicability and Definitions

This License applies to any manual or other work that contains a notice placed by the copyright holder saying it can be distributed under the terms of this License. The "Document," below, refers to any such manual or work. Any member of the public is a licensee, and is addressed as "you."

A "Modified Version" of the Document means any work containing the Document or a portion of it, either copied verbatim, or with modifications and/or translated into another language.

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The "Invariant Sections" are certain Secondary Sections whose titles are designated, as being those of Invariant Sections, in the notice that says that the Document is released under this License.

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Examples of suitable formats for Transparent copies include plain ASCII without markup, Texinfo input format, \LaTeX~input format, SGML or XML using a publicly available DTD, and standard-conforming simple HTML designed for human modification. Opaque formats include PostScript, PDF, proprietary formats that can be read and edited only by proprietary word processors, SGML or XML for which the DTD and/or processing tools are not generally available, and the machine-generated HTML produced by some word processors for output purposes only.

The "Title Page" means, for a printed book, the title page itself, plus such following pages as are needed to hold, legibly, the material this License requires to appear in the title page. For works in formats which do not have any title page as such, "Title Page" means the text near the most prominent appearance of the work's title, preceding the beginning of the body of the text.

[modifier] Verbatim Copying

You may copy and distribute the Document in any medium, either commercially or noncommercially, provided that this License, the copyright notices, and the license notice saying this License applies to the Document are reproduced in all copies, and that you add no other conditions whatsoever to those of this License. You may not use technical measures to obstruct or control the reading or further copying of the copies you make or distribute. However, you may accept compensation in exchange for copies. If you distribute a large enough number of copies you must also follow the conditions in Section 3.

You may also lend copies, under the same conditions stated above, and you may publicly display copies.

[modifier] Copying in Quantity

If you publish printed copies of the Document numbering more than 100, and the Document's license notice requires Cover Texts, you must enclose the copies in covers that carry, clearly and legibly, all these Cover Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on the back cover. Both covers must also clearly and legibly identify you as the publisher of these copies. The front cover must present the full title with all words of the title equally prominent and visible. You may add other material on the covers in addition. Copying with changes limited to the covers, as long as they preserve the title of the Document and satisfy these conditions, can be treated as verbatim copying in other respects.

If the required texts for either cover are too voluminous to fit legibly, you should put the first ones listed (as many as fit reasonably) on the actual cover, and continue the rest onto adjacent pages.

If you publish or distribute Opaque copies of the Document numbering more than 100, you must either include a machine-readable Transparent copy along with each Opaque copy, or state in or with each Opaque copy a publicly accessible computer-network location containing a complete Transparent copy of the Document, free of added material, which the general network-using public has access to download anonymously at no charge using public-standard network protocols. If you use the latter option, you must take reasonably prudent steps, when you begin distribution of Opaque copies in quantity, to ensure that this Transparent copy will remain thus accessible at the stated location until at least one year after the last time you distribute an Opaque copy (directly or through your agents or retailers) of that edition to the public.

It is requested, but not required, that you contact the authors of the Document well before redistributing any large number of copies, to give them a chance to provide you with an updated version of the Document.

[modifier] Modifications

You may copy and distribute a Modified Version of the Document under the conditions of Sections 2 and 3 above, provided that you release the Modified Version under precisely this License, with the Modified Version filling the role of the Document, thus licensing distribution and modification of the Modified Version to whoever possesses a copy of it. In addition, you must do these things in the Modified Version:

Use in the Title Page (and on the covers, if any) a title distinct from that of the Document, and from those of previous versions (which should, if there were any, be listed in the History section of the Document). You may use the same title as a previous version if the original publisher of that version gives permission.

List on the Title Page, as authors, one or more persons or entities responsible for authorship of the modifications in the Modified Version, together with at least five of the principal authors of the Document (all of its principal authors, if it has less than five).

State on the Title page the name of the publisher of the Modified Version, as the publisher.

Preserve all the copyright notices of the Document.

Add an appropriate copyright notice for your modifications adjacent to the other copyright notices.

Include, immediately after the copyright notices, a license notice giving the public permission to use the Modified Version under the terms of this License, in the form shown in the Addendum below.

Preserve in that license notice the full lists of Invariant Sections and required Cover Texts given in the Document's license notice.

Include an unaltered copy of this License.

Preserve the section entitled "History," and its title, and add to it an item stating at least the title, year, new authors, and publisher of the Modified Version as given on the Title Page. If there is no section entitled "History" in the Document, create one stating the title, year, authors, and publisher of the Document as given on its Title Page, then add an item describing the Modified Version as stated in the previous sentence.

Preserve the network location, if any, given in the Document for public access to a Transparent copy of the Document, and likewise the network locations given in the Document for previous versions it was based on. These may be placed in the "History" section. You may omit a network location for a work that was published at least four years before the Document itself, or if the original publisher of the version it refers to gives permission.

In any section entitled "Acknowledgements" or "Dedications," preserve the section's title, and preserve in the section all the substance and tone of each of the contributor acknowledgements and/or dedications given therein.

Preserve all the Invariant Sections of the Document, unaltered in their text and in their titles. Section numbers or the equivalent are not considered part of the section titles.

Delete any section entitled "Endorsements." Such a section may not be included in the Modified Version.

Do not retitle any existing section as "Endorsements" or to conflict in title with any Invariant Section.

If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document, you may at your option designate some or all of these sections as invariant. To do this, add their titles to the list of Invariant Sections in the Modified Version's license notice. These titles must be distinct from any other section titles.

You may add a section entitled "Endorsements," provided it contains nothing but endorsements of your Modified Version by various parties---for example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard.

You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; but you may replace the old one, on explicit permission from the previous publisher that added the old one.

The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.

[modifier] Combining Documents

You may combine the Document with other documents released under this License, under the terms defined in Section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice.

The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.

In the combination, you must combine any sections entitled "History" in the various original documents, forming one section entitled "History"; likewise combine any sections entitled "Acknowledgements," and any sections entitled "Dedications." You must delete all sections entitled "Endorsements."

[modifier] Collections of Documents

You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.

You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.

1.10.3.a.7Aggregation with Independent Works

A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, does not as a whole count as a Modified Version of the Document, provided no compilation copyright is claimed for the compilation. Such a compilation is called an "aggregate," and this License does not apply to the other self-contained works thus compiled with the Document, on account of their being thus compiled, if they are not themselves derivative works of the Document.

If the Cover Text requirement of Section 3 is applicable to these copies of the Document, then if the Document is less than one quarter of the entire aggregate, the Document's Cover Texts may be placed on covers that surround only the Document within the aggregate. Otherwise they must appear on covers around the whole aggregate.

[modifier] Translation

Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of Section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License provided that you also include the original English version of this License. In case of a disagreement between the translation and the original English version of this License, the original English version will prevail.

[modifier] Termination

You may not copy, modify, sublicense, or distribute the Document except as expressly provided for under this License. Any other attempt to copy, modify, sublicense, or distribute the Document is void, and will automatically terminate your rights under this License. However, parties who have received copies, or rights, from you under this License will not have their licenses terminated so long as such parties remain in full compliance.

[modifier] Future Revisions of This License

The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See http:///www.gnu.org/copyleft/.

Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License "or any later version" applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation.