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Python Avancé

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  1. Les modules en Python
  2. Le module OS
  3. Gestion des fichiers en Python
  4. Fichier de configuration .ini
  5. Python et bases de données SQLite
  6. Python et bases de données MySql
  7. DB Browser for SQLite
  8. Interface Graphique avec Tkinter
  9. La bibliothèque d'images PILLOW
  10. Le module de style tkinter.ttk
  11. Projet: Création d'un éditeur de texte
  12. Interface graphique avec wxPython
  13. Le framework Django

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Archives mensuelles : novembre 2016

1 – Notions d’alphabets, mots & langages

\chapter{Langages et automates} \section{Alphabets, Mots et Langages} \section{Notion pr\'{e}liminaires} \subsection{D\'{e}finitions et notations} \begin{definition} Un alphabet est un ensemble fini quelconque non vide. Les \'{e}l\'{e}ments d'un alphabet sont appel\'{e}s des \textbf{lettres }ou\textbf{\ Symbols}. \end{definition} \begin{notation} Un alphabet sera not\'{e} en g\'{e}n\'{e}ral par la lettre grec $\ \sum $ \end{notation} \begin{definition} Un mot est une suite finie de lettres \end{definition} \begin{example} $\sum =\{a,b,c,\ldots ,z\}$ est un alphabet , $a,b,c,$ \ldots\ sont des lettres, \textbf{math,cpr, oujda},\ldots\ sont des mots \end{example} \begin{notation} L'ensemble des mots sur $\sum $ \ sera not\'{e} $\sum^{\ast }$ \end{notation} \begin{example} $\sum =\{0,1,2,...\}=% %TCIMACRO{\U{2115} }% %BeginExpansion \mathbb{N} %EndExpansion $ \ est un alphabet , $484,275,107,...$ \ sont des mots \end{example} \begin{notation} Le mot qui ne contient aucune lettre est appel\'{e} le mot vide not\'{e} $% \Lambda $ \end{notation} \begin{remark} On s'interesse seulement \`{a} la forme d'un mot qui peut \^{e}tre qq et on omet le sens du mot exemple : avhbrtys, jorbqhegd,... sont des mots. \end{remark} \begin{definition} La longueur d'un mot $x$ not\'{e} $|x|$ est le nombre de symbols qui le compose exemple si $x=arbre$ alors $|x|=5$ \end{definition} \begin{notation} Soit $x$ un mot de $\sum^{\ast }$ et $\sigma $ une lettre de $\sum $ le nombre d'apparition de \ $\sigma $\ dans $x$\ est not\'{e} $|x|_{\sigma }$ \end{notation} \begin{example} $|arbre|_{r}=2,$ \ $|arbre|_{a}=1$ ,\ $|abbcb|_{b}=3$ \end{example}

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Buying The Right Notebook Computer
This article describes the main features one should look while purchasing a notebook. Also it talks about the problem of hardware upgrade.
By: Roberto Sedycias

Ipod Most Popular Mp3 Mp4 player
This article describes the many iPods generations and features that made this product one of the most popular mp3 mp4 players of all times.
By: Roberto Sedycias

A Brief History Of iPod
This article is a brief history of iPod. It describes how it started, the goals for this music player and how the name iPod came into being.
By: Roberto Sedycias

How To Select The Notebook That Meets Your Requirements?
This article explains about notebooks and its many different models. Also it guides the buyer thru steps that might be helpful in making a good purchase.
By: Roberto Sedycias

Is Notebook A Better Choice Than Desktop?
This article makes a comparison between notebooks and desktop computers. It also describes the advantages and benefits of using notebooks.
By: Roberto Sedycias

Find Real China Wholesale Distributors for MP3 Players
Chinese firms are producing and exporting popular electronics such as MP3 players that are high in quality and affordable.
By: chinavasion

iPod Facts You Should Know
This article provides lots of information about iPod. It talks about the many iPod generations and its main features, as well as multimedia capability.
By: Roberto Sedycias

A Purchase Guide to Budget Notebooks
This article explains about budget notebooks, its configurations and main features, as a viable mobile solution for one’s computer related tasks. Several manufacturer models are compared for better understanding.
By: Roberto Sedycias

Understanding Mp4 Players
This article explains the basic difference between mp3 and mp4 players, together with the main features of mp4 devices. Internet browsing, emailing and video shows are all resources available in the mp4 players.
By: Roberto Sedycias

Notebook or Desktop Computer, What is the Best Buy?
This article explains the main differences between notebooks and desktops, providing useful information about as to which one would be best to purchase. Also there is some information about reconditioned computers.
By: Roberto Sedycias

Buying Guide to Graphics Cards
The graphics card is a vital performance component of your computer, particularly if you play 3D games, or work with graphics and video content.
By: Andrew Gates

Guide to Buying a Webcam
Before you make a choice about any webcam equipment, it helps to decide exactly how you want to use the technology.
By: Andrew Gates

Guide to Buying Hard Drives
How to shop for an internal or external drive like a pro.
By: Andrew Gates

How to Build a PC

Do you know what could beat the exciting feeling of having a new computer? Make your own PC!

By: pazzer

Skype Lets You Make Free Phone Calls Online

Skype, the Internet telephony company that set the traditional telephone world on its ear. You can make reliable calls using the Internet for anywhere from 0 to 2.3-cents per minute. Recently purchased by Ebay for 2.6 billion dollars, Skype stands ready to revolutionize worldwide voice communication because they enable you to carry on crystal clear voice communication with anyone else in the world with a either a phone or Internet connection.

By: Jim Edwards

How to ‘Download’ Your Old Computer to the Highest Bidder

When you think trash, you surely don’t think about your old, trusty personal computer. But that’s exactly what will become of it when you make the inevitable move toward your next laptop or desktop. And, yes, buying a new computer is inevitable, considering the pace at which computer technology zips along. Just think—about a handful of years ago, a fast microprocessor for a laptop was at 233 MHz. Now you’re looking at about at least 2 GHz! That’s Giga, with a G.

By: Donald Lee

What Is VoIP Security?

A Practical Introduction to VoIP Security

By: Laura Rupert

What Is A VoIP Gateway?

A Practical Introduction to VoIP Gateways

By: Laura Rupert

How Do I Compare VoIP providers?

Practical and impartial advice on how to compare VoIP providers.

By: Laura Rupert

How Does VoIP Work?

A Practical Introduction to VoIP

By: Laura Rupert

Where Can I Get VoIP Training?

Practice advice on finding training for the new and exciting VoIP technologies.

By: Laura Rupert

What Is A VoIP Router?

A Practical Introduction to VoIP Routers

By: Laura Rupert

Blu-Ray set to take the world by storm!

The Blu-ray Disc belongs to a new generation of optical discs capable of staging high density data. Operating at a wave length of 405nm unlike DVDs and CDs that are based on red/IR lasers that work at 650 and 780nm,blue-ray discs store much more data

By: Paul Colbert

Free Website Content » Computers » Computer Hardware Articles

By: Paul Colbert

The Blu-ray Disc belongs to a new generation of optical discs capable of staging high density data. Blu-Ray technology is based on a blue-violet coloured laser. The blue laser operates at a wave length of 405 nm, while older technology such as DVDs and CDs are based on red and infrared lasers that works at 650 and 780 nm. Since the wave length is shorter with a blue laser, the new Blu-ray technology makes is possible to store much more information

The advantage with the Blu-ray technology is that the laser beam can be focused much more tightly at the surface of the disc. Tight focus means that a smaller spot will be produced on the surface on the disc, and when the spots become smaller there will naturally be room for more information on each disc. The minimum spot size of any laser depends on a naturally accruing phenomenon called diffraction. The narrow beam of light sent out from a laser will always diverge into a wider beam eventually, due to the natural diffraction of waves. Diffraction will also occur the waves meet an obstruction. By reducing the wavelength of a laser, we can affect the diffraction.

In Blu-ray technology, the diffractions is also affected by the fact that the lens used to focus the light has a higher numerical aperture than the lenses found in ordinary DVDs – 0.85 instead of 0.6. Blu-ray technology based appliances are also equipped with a dual-lens system of supreme quality, and the cover layer has been made thinner in order to prevent unwanted optical effects. All this makes it possible for a Blu-ray laser to focus on much smaller spots. The optical improvements are accompanied with a new method for encoding data which makes it possible to store even more data on the Blu-ray disc.

The standard for Blu-ray technology has been developed as a joint venture between several major manufacturers of PCs and consumer electronics, including Sony and Philips. The group is called the Blu-ray Disc Association (BDA). The first Blu-ray recorder was launched in Japan in 2003, by Sony. Today, Samsung, JVC, Matsushita (Panasonic) and LG Electronics are all examples of companies using Blu-ray technology in their products. Hewlett Packard has announced that they will release desktop PCs equipped with Blu-ray technology in late 2005.

The main competitor for the Blu-ray technology is the HD DVD format which is also capable of storing more information than a normal DVD. The Blu-ray technology does however allow for more information per layer than the HD DVD format – 25 GB compared to 15 GB. The Blu-ray technology will on the other hand most likely be more expensive to support, at least initially, which can make the HD DVD a tempting alternative. In a Blu-ray disc, the data is stored extremely close to the surface. This made the first Blu-ray discs extremely vulnerable to scratching and many users preferred the tougher HD DVD discs. Since 2004, all Blu-ray discs are coated with a clear polymer called « Durabis » which makes them much more durable. According to the developers of Durabis, the TDK Corporation, a coated Blu-ray disc will work even after being attacked with a screwdriver.

Author Bio

Paul Colbert of Blu Ray World is an author of various articles relating to new technology and innovations.

Article Source: – Free Website Content

Related Computer Hardware Articles

©2006 Free Website Content – All Rights Reserved

Free Website Content » Computers » Computer Hardware Articles

By: Laura Rupert

Voice over Internet Protocol (VoIP – is a new way to talk on your phone through your broadband internet connection. A VoIP router is needed to help you use the same phone you have been using before your VoIP connection. If you have voice over internet protocol available to you, you’ll need a router to sort of make it all happen. It’s a small device that will take a little time to get used to, but once you’ve used it just a couple times you’ll be able to use the whole system without a second thought.

Without a VoIP router your phone will not be able to figure out where datagrams should go from source to destination, so information will be lost. Routers will help control phone traffic, controls and maintains bandwidth, and ensures a good voice quality for each and every phone call. Basically, router is responsible for routing all the information in and out of your home so that you can get the services you are supposed to get.

It’s said that because of ever expanding technology that VoIP routers won’t be needed for much longer. With the invention of digital telephones the need for a separate router won’t be necessary. But, until this newer technology becomes more widespread and cost efficient, the majority of VoIP users will need a router to use the voice over internet protocol features. Because of this newer technology, having VoIP service will become easier and more accessible to everyone in the very near future. But, don’t let the idea of a routing device scare you off, as VoIP is very easy to use!

Author Bio

Laura Rupert is a freelance writer who contributes to The Tech FAQ

Article Source: – Free Website Content

Related Computer Hardware Articles

©2006 Free Website Content – All Rights Reserved

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