Comment Utiliser Le Shell Python

Lorsque vous commencez à apprendre un nouveau langage de programmation, votre tout premier programme est susceptible d'être celui qui affiche "hello world!".

Disons que vous voulez faire cela en Python. Il y a deux façons de le faire : utiliser le shell Python ou l'écrire en tant que script et l'exécuter dans le terminal.

Qu'est-ce qu'une coque ?

Un système d'exploitation est composé d'un ensemble de programmes. Ils effectuent des tâches telles que la gestion des fichiers, la gestion de la mémoire et la gestion des ressources, et ils aident vos applications à fonctionner correctement.

Tout le travail que nous faisons sur ordinateur, comme analyser des données dans Excel ou jouer à des jeux, est facilité par le système d'exploitation.

Les programmes du système d'exploitation sont de deux types, appelés programmes shell et noyau .

Les programmes du noyau sont ceux qui exécutent les tâches réelles, comme la création d'un fichier ou l'envoi d'interruptions. Shell est un autre programme dont le travail consiste à prendre des entrées, à décider et à exécuter le programme du noyau requis pour effectuer le travail et afficher la sortie.

Le shell est également appelé processeur de commandes .

Qu'est-ce qu'une borne ?

Le terminal est le programme qui interagit avec le shell et nous permet de communiquer avec lui via des commandes textuelles. C'est pourquoi on l'appelle aussi la ligne de commande.

Pour accéder au terminal sous Windows, appuyez sur le logo Windows + R, tapez cmd et appuyez sur Entrée.

Pour accéder au terminal sur Ubuntu, appuyez sur Ctrl + Alt + T.

Qu'est-ce que le shell Python ?

Python est un langage interprété. Cela signifie que l'interpréteur Python lit une ligne de code, exécute cette ligne, puis répète ce processus s'il n'y a pas d'erreurs.

Le shell Python vous offre une interface de ligne de commande que vous pouvez utiliser pour spécifier des commandes directement à l'interpréteur Python de manière interactive.

Vous pouvez obtenir de nombreuses informations détaillées sur le shell Python dans la documentation officielle .

Comment utiliser le shell Python

Pour démarrer le shell Python, tapez simplement pythonet appuyez sur Entrée dans le terminal :

C:\Users\Suchandra Datta>python
Python 3.8.3 (tags/v3.8.3:6f8c832, May 13 2020, 22:37:02) [MSC v.1924 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>>print("hello world!")

Le shell interactif est également appelé REPL qui signifie lire, évaluer, imprimer, boucler. Il lira chaque commande, l'évaluera et l'exécutera, imprimera la sortie de cette commande, le cas échéant, et continuera ce même processus à plusieurs reprises jusqu'à ce que vous quittiez le shell.

Il existe différentes manières de quitter le shell :

• vous pouvez appuyer sur Ctrl+Z sous Windows ou Ctrl+D sur les systèmes Unix pour quitter
• utilisez la commande exit()
• utilisez la commande quit()

C:\Users\Suchandra Datta>python
Python 3.8.3 (tags/v3.8.3:6f8c832, May 13 2020, 22:37:02) [MSC v.1924 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> print("HELLO WORLD")
HELLO WORLD
>>> quit()

C:\Users\Suchandra Datta>

C:\Users\Suchandra Datta>python
Python 3.8.3 (tags/v3.8.3:6f8c832, May 13 2020, 22:37:02) [MSC v.1924 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> exit()

C:\Users\Suchandra Datta>

C:\Users\Suchandra Datta>python
Python 3.8.3 (tags/v3.8.3:6f8c832, May 13 2020, 22:37:02) [MSC v.1924 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> ^Z


C:\Users\Suchandra Datta>

Que pouvez-vous faire dans le shell Python ?

Vous pouvez faire à peu près tout ce que le langage Python permet, de l'utilisation de variables, de boucles et de conditions à la définition de fonctions, etc.

Il >>>s'agit de l'invite du shell où vous tapez vos commandes. Si vous avez des commandes qui s'étendent sur plusieurs lignes - par exemple lorsque vous définissez des boucles - le shell imprime les ...caractères qui signifient qu'une ligne continue.

Voyons un exemple :

>>>
>>> watch_list = ["stranger_things_s1", "stranger_things_s2", "stranger_things_s3","stranger_things_s4"]
>>>
>>>

Ici, nous avons défini une liste avec des noms d'émissions de télévision via le shell Python.

Ensuite, définissons une fonction qui accepte une liste d'émissions et renvoie aléatoirement une émission :

>>> def weekend_party(show_list):
...     r = random.randint(0, len(show_list)-1)
...     return show_list[r]
...

Notez les lignes de continuation ( ...) du shell Python ici.

Enfin pour invoquer la fonction depuis le shell, il vous suffit d'appeler la fonction comme vous le feriez dans un script :

>>> weekend_party(watch_list)
'stranger_things_s1'
>>>
>>>
>>> weekend_party(watch_list)
'stranger_things_s3'
>>>
>>>
>>> weekend_party(watch_list)
'stranger_things_s2'
>>>
>>>
>>> weekend_party(watch_list)
'stranger_things_s2'
>>>
>>>
>>> weekend_party(watch_list)
'stranger_things_s3'
>>>

Vous pouvez inspecter les modules Python à partir du shell, comme indiqué ci-dessous :

>>>
>>>
>>> import numpy
>>> numpy.__version__
'1.20.1'
>>>

Vous pouvez voir quelles méthodes et quels attributs un module offre en utilisant la dir()méthode :

>>>
>>> x = dir(numpy)
>>> len(x)
606
>>> x[0:3]
['ALLOW_THREADS', 'AxisError', 'BUFSIZE']

Ici, vous pouvez voir que Numpy a 606 méthodes et propriétés au total.

Comment exécuter des scripts Python

Le shell Python est utile pour exécuter des programmes simples ou pour déboguer des parties de programmes complexes.

Mais de très gros programmes Python avec beaucoup de complexité sont écrits dans des fichiers avec une extension .py, généralement appelés scripts Python. Ensuite, vous les exécutez depuis le terminal à l'aide de la Pythoncommande.

La syntaxe usuelle est :

python filename.py

Toutes les commandes que nous avons exécutées précédemment via le shell, nous pouvons également les écrire dans un script et les exécuter de cette manière.

Conclusion

Dans cet article, nous avons découvert le shell, le terminal, comment utiliser le shell Python. Nous avons également vu comment exécuter des scripts Python à partir de la ligne de commande.

J'espère que cet article vous aidera à comprendre ce qu'est le shell Python et comment vous pouvez l'utiliser dans votre vie de tous les jours. Bon apprentissage! 

Source : https://www.freecodecamp.org/news/run-python-script-how-to-execute-python-shell-commands-in-terminal/

#python

What is GEEK

Buddha Community

Why use Python for Software Development

No programming language is pretty much as diverse as Python. It enables building cutting edge applications effortlessly. Developers are as yet investigating the full capability of end-to-end Python development services in various areas. 

By areas, we mean FinTech, HealthTech, InsureTech, Cybersecurity, and that's just the beginning. These are New Economy areas, and Python has the ability to serve every one of them. The vast majority of them require massive computational abilities. Python's code is dynamic and powerful - equipped for taking care of the heavy traffic and substantial algorithmic capacities. 

Programming advancement is multidimensional today. Endeavor programming requires an intelligent application with AI and ML capacities. Shopper based applications require information examination to convey a superior client experience. Netflix, Trello, and Amazon are genuine instances of such applications. Python assists with building them effortlessly. 

5 Reasons to Utilize Python for Programming Web Apps 

Python can do such numerous things that developers can't discover enough reasons to admire it. Python application development isn't restricted to web and enterprise applications. It is exceptionally adaptable and superb for a wide range of uses.

Robust frameworks 

Python is known for its tools and frameworks. There's a structure for everything. Django is helpful for building web applications, venture applications, logical applications, and mathematical processing. Flask is another web improvement framework with no conditions. 

Web2Py, CherryPy, and Falcon offer incredible capabilities to customize Python development services. A large portion of them are open-source frameworks that allow quick turn of events. 

Simple to read and compose 

Python has an improved sentence structure - one that is like the English language. New engineers for Python can undoubtedly understand where they stand in the development process. The simplicity of composing allows quick application building. 

The motivation behind building Python, as said by its maker Guido Van Rossum, was to empower even beginner engineers to comprehend the programming language. The simple coding likewise permits developers to roll out speedy improvements without getting confused by pointless subtleties. 

Utilized by the best 

Alright - Python isn't simply one more programming language. It should have something, which is the reason the business giants use it. Furthermore, that too for different purposes. Developers at Google use Python to assemble framework organization systems, parallel information pusher, code audit, testing and QA, and substantially more. Netflix utilizes Python web development services for its recommendation algorithm and media player. 

Massive community support 

Python has a steadily developing community that offers enormous help. From amateurs to specialists, there's everybody. There are a lot of instructional exercises, documentation, and guides accessible for Python web development solutions. 

Today, numerous universities start with Python, adding to the quantity of individuals in the community. Frequently, Python designers team up on various tasks and help each other with algorithmic, utilitarian, and application critical thinking. 

Progressive applications 

Python is the greatest supporter of data science, Machine Learning, and Artificial Intelligence at any enterprise software development company. Its utilization cases in cutting edge applications are the most compelling motivation for its prosperity. Python is the second most well known tool after R for data analytics.

The simplicity of getting sorted out, overseeing, and visualizing information through unique libraries makes it ideal for data based applications. TensorFlow for neural networks and OpenCV for computer vision are two of Python's most well known use cases for Machine learning applications.

Summary

Thinking about the advances in programming and innovation, Python is a YES for an assorted scope of utilizations. Game development, web application development services, GUI advancement, ML and AI improvement, Enterprise and customer applications - every one of them uses Python to its full potential. 

The disadvantages of Python web improvement arrangements are regularly disregarded by developers and organizations because of the advantages it gives. They focus on quality over speed and performance over blunders. That is the reason it's a good idea to utilize Python for building the applications of the future.

#python development services #python development company #python app development #python development #python in web development #python software development

Statements And Comments In Python

When you write a program in python that particular code is written line by line. Which means there are kind of sentences in your code. These sentences can be identified under two main groups according to the reason why you are adding them into your code.

To make it easy for you I will name them as Python statements and Python comments.

Python Statements

Instructions that you write in your code and that a **Python interpreter **can execute are called statements.

Wait what! Python interpreter? What’s that?

Let me make it clear to you.

Python interpreter is nothing but a converter which converts the Python language to machine language. Your computer’s hardware obviously can’t understand Python. Therefore, there has to be something that makes the computer understand what you want to be done using your Python code. That is basically done by the Python interpreter. Piece of cake!

Still no idea what really Python statements are?

Don’t worry! Help is on the way!

#python-programming #comments-in-python #statements-in-python #python-comments #python-statements

Python Tricks Every Developer Should Know

Python is awesome, it’s one of the easiest languages with simple and intuitive syntax but wait, have you ever thought that there might ways to write your python code simpler?

In this tutorial, you’re going to learn a variety of Python tricks that you can use to write your Python code in a more readable and efficient way like a pro.

Let’s get started

Swapping value in Python

Instead of creating a temporary variable to hold the value of the one while swapping, you can do this instead

>>> FirstName = "kalebu"
>>> LastName = "Jordan"
>>> FirstName, LastName = LastName, FirstName 
>>> print(FirstName, LastName)
('Jordan', 'kalebu')

#python #python-programming #python3 #python-tutorials #learn-python #python-tips #python-skills #python-development

How to Remove all Duplicate Files on your Drive via Python

Today you’re going to learn how to use Python programming in a way that can ultimately save a lot of space on your drive by removing all the duplicates.

Intro

In many situations you may find yourself having duplicates files on your disk and but when it comes to tracking and checking them manually it can tedious.

Heres a solution

Instead of tracking throughout your disk to see if there is a duplicate, you can automate the process using coding, by writing a program to recursively track through the disk and remove all the found duplicates and that’s what this article is about.

But How do we do it?

If we were to read the whole file and then compare it to the rest of the files recursively through the given directory it will take a very long time, then how do we do it?

The answer is hashing, with hashing can generate a given string of letters and numbers which act as the identity of a given file and if we find any other file with the same identity we gonna delete it.

There’s a variety of hashing algorithms out there such as

• md5
• sha1
• sha224, sha256, sha384 and sha512

#python-programming #python-tutorials #learn-python #python-project #python3 #python #python-skills #python-tips

How To Compare Tesla and Ford Company By Using Magic Methods in Python

Magic Methods are the special methods which gives us the ability to access built in syntactical features such as ‘<’, ‘>’, ‘==’, ‘+’ etc…

You must have worked with such methods without knowing them to be as magic methods. Magic methods can be identified with their names which start with __ and ends with __ like init, call, str etc. These methods are also called Dunder Methods, because of their name starting and ending with Double Underscore (Dunder).

Now there are a number of such special methods, which you might have come across too, in Python. We will just be taking an example of a few of them to understand how they work and how we can use them.

1. init

class AnyClass:
    def __init__():
        print("Init called on its own")
obj = AnyClass()

The first example is _init, _and as the name suggests, it is used for initializing objects. Init method is called on its own, ie. whenever an object is created for the class, the init method is called on its own.

The output of the above code will be given below. Note how we did not call the init method and it got invoked as we created an object for class AnyClass.

Init called on its own

2. add

Let’s move to some other example, add gives us the ability to access the built in syntax feature of the character +. Let’s see how,

class AnyClass:
    def __init__(self, var):
        self.some_var = var
    def __add__(self, other_obj):
        print("Calling the add method")
        return self.some_var + other_obj.some_var
obj1 = AnyClass(5)
obj2 = AnyClass(6)
obj1 + obj2

#python3 #python #python-programming #python-web-development #python-tutorials #python-top-story #python-tips #learn-python