Here in this blog, you will learn about the basic fundamentals of how to use python from a beginner’s point of view. If you want to start learning python but aren’t sure where to start it. So in that case, you arrive at the right place, here you will know the basics of python programming like what python is, how to use python and why you should use it, its features, etc.
What is Python?
Python is a programming language which is free and also easy to learn. Its main characteristics or features are that it is a high-level, dynamically typed, and interpretable programming language. So because of this the error debugging is easier and it also encourages the rapid development of application prototypes, and making itself as the language choice for programmers to code with. It was developed by the Guido Van Rossum in 1989, who emphasised the DRY (Don’t Repeat Yourself) principle and readability.
Why Should You Use Python?
The flexibility of the python allows you to do a wide range of small tasks as well as the large one’s. By using python you can write the programs like the basic one’s or also the large or complex enterprise solutions. Before you know how to use python, you should know why you should use python. In the world of computer programming, you can find python everywhere.
Here are some sampling of its uses:
- It is used to create desktop applications, such as GUI (graphical user interfaces) applications, CLI (Command line interfaces) tools, and even games
- It is used to analyze the data mathematically and scientifically
- It is used for the development of web and internet applications
- It is used for doing the computer systems administration and also for the automating tasks
- It is used for performing the DevOps tasks
Features of the Python
There are so many features of the python which makes it attractive and makes itself as the first choice for the programming language:
- Python is available for free, even if you choose to use it for commercial purposes.
- Python is an open source, therefore anyone can contribute to its development.
- Python is accessible to the people of all ages, like from the children who are going to school to the retirees, and you can learn it too.
- Python is versatile, and it can be used for allowing you to solve the problems in a variety of areas such as scripting, data science, web development, GUI development, and more.
- Python is powerful and with the help of it, you can code the small scripts as well as the complex or large scale enterprise solutions.
The following are some features of the python over the other programming languages:
- Interpreted: It is interpreted so it is portable and quicker to experiment as compared to the other compiled languages.
- Multiparadigm: It allows you to write code in a number of different styles, such as object-oriented, imperative, and functional.
- Dynamically typed: At runtime, it checks the variables, so you don’t need to declare them explicitly.
- Strongly typed: It won’t let unsafe operations on types that aren’t compatible go unnoticed.
How to Download and Install Python
Python runs on Linux, Mac, Windows, and a variety of other operating systems. On macOS and most Linux distributions, it comes preinstalled. However, you can download and install the most recent version to stay up to date. In the different kinds of projects, you can also choose to use different python versions.
If you want to know or want to check which python version is globally installed in your operating system. Then simply open the terminal or the command line and run or type the following command to see about the version.
$ python3 -V
By using this command it displays the version of the default python 3 installation on your system. This is because some operating systems still include Python 2 as their default Python installation, you must use python3 instead of python.
Installing Python From Binaries
Download the appropriate version from the official site of the python regardless of your operating system. Go there and download the 32-bit or 64-bit version that corresponds to your operating system and processor.
It’s always a good idea to choose and download a Python binary from the official website of the language. Some OS-specific alternatives are the following:
- macOS: You have a option of Homebrew from where you can install the python
- Linux: By using the distribution’s package manager you can install the several python versions.
- Windows: You have the microsoft store from where you can install the python.
Also you can install Python along with the large number of packages and libraries by using the Anaconda distribution, or if you only want to install only those packages you need, then you can use Miniconda also.
Running Your Python Interpreter
To ensure that the python is installed properly or not, you can run a quick test. Run the command python3 from your terminal or command line. After running this command, there should open a python interactive session, and the command prompt which opened, it should be like this:
>>> Python 3.9.0 (default, Oct 5 2020, 17:52:02) [GCC 9.3.0] on linux Type "help", "copyright", "credits" or "license" for more information. >>> While you’re here, you should run the first line of your code: >>> >>> print("Python is easy!") Python is easy!
After writing your python program or when you are done with it you can leave the interactive session by using the exit () or quit (). Also you can use the following key combinations which are shown below:
- macOS and Linux: Ctrl+D
- Windows: Ctrl+D and then press Enter
The Basic Python Syntax
Python syntax is simple, concise, and easy to understand. One of the most appealing features of the language is its readability. So because of this, python is therefore an ideal for the people who are starting to learn to program. You can see and learn about the several key components of the python syntax in this section, and that key components are the following which are shown below:
- Built-in data types
- Conditional statements
And the knowledge you gain from here will definitely help you to get up and running with python.
Comments are the text that lives in your code but when the python interpreter runs the code, then it is ignored by it. To explain the code to yourself and other developers, you can use comments, so that you and they both understand what it does and why the code is written in this way. You can simply add a hash mark (#) before your comment text to make a comment in Python:
# This is the example of comment line
The text which is written after the hash mark and up to the end of the line is ignored by the python interpreter. Inline comments can also be added to your code. In other words, if the comment occupies the last part of the line, then you can combine the statement or the python expression with a comment in the single line:
var = "Hello" # This is an inline comment
To clarify the code that isn’t apparent on its own, inline comments should be used there. In general, keep your comments brief and to the point. According to Python Enhancement Proposal (PEP) 8 advise, keep comments to 72 characters or less. You may want to break it up into several lines, if your comment is close to or longer than that:
# The comment which is long and requires # two lines to complete.
By using the hash mark you can use the several lines, if you need more space for a comment. If your comment is long, then in this way you can keep your comments under 72 characters.
In the python, the names which are attached to a particular object are the variables. In the memory address, they keep a reference, or pointer where an object is stored. The object can be accessed by using the variable name, once a variable has been assigned to an object.
Variables should be defined in advance. Here’s the syntax:
variable_name = variable_value
You should use the name of your variables in a way that is both intuitive as well as readable. The name of the variable should give some indication to the values that have been assigned to it.
In other contexts, you should avoid single-character names and use something more descriptive. That way, other developers can make an educated guess of what your variables hold. Think of others, as well as your future self, when writing your programs. Your future self will thank you.
Sometimes some programmers use the variable names short, like a and b. These names are excellent for subjects like math, algebra and other related subjects. In other situations, you should use something more descriptive as compared to using the single-character names. So with the help of the descriptive name, other developers will be able to make an educated guess as to what your variables contain.
Here is the examples of variable names in Python:
>>> numbers = [8, 5, 9, 6, 2] >>> numbers [8, 5, 9, 6, 2] >>> first_num = 8 >>> first_num 8
Your variable names may include uppercase and lowercase letters (A-Z, a-z), digits (0-9), and the underscore character (_). And variable names should be alphanumeric, however, the first character of the name must not be a digit.
Python has a set of the special words that are the part of its syntax, like any other programming language. Keywords are the terms used to describe these words.
You can run the following code in an interactive session to get the full list of keywords available in your current Python installation:
>>> >>> help("keywords") Here is a list of the Python keywords. Enter any keyword to get more help. False class from or None continue global pass True def if raise and del import return as elif in try assert else is while async except lambda with await finally nonlocal yield break for not
In the python syntax, each of these keywords has a specific function. They are the reserved words in the language with special meanings and purposes, and you can not use them for anything other than these purposes. For example, in your code, you shouldn’t use them as variable names.
Built-In Data Types
There are many built-in data types in the python and those built-in data types are the following:
- Numbers: (Integer, Floats, Complex)
Sometimes you need to run or not to run the given code block, all it depends on some certain conditions, which met or not. So, in this type of the case, conditional statements will help you. So based on an expression’s truth value, these conditional statements control the execution of the set of statements.
Here are some examples of this type of if statement:
if <expr>: <statement(s)> else: <statement(s)>
If <expr> is true, the first suite is executed, and the second is skipped. If <expr> is false, the first suite is skipped and the second is executed.
>>> a = 2 >>> if a < 8: ... print('(first suite)') ... print(a is small') ... else: ... print('(second suite)') ... print('a is large') ... (first suite) a is small
To get a final result, if you need to repeat a piece of code several times, then you would need to use a loop. Loops are a common method of iterating multiple times while performing some actions each time. There are two types of loops which comes in python that are the:
- For loops: For definite iteration, to perform a set number or repetitions, for loops are used.
- While loops: For indefinite iteration, or to repeat until the given condition is met.
Here are some examples of this type of “for loop”:
for <var> in <iterable>: <statement(s)>
Here is a representative example:
>>> x = ['abc', 'xyz', 'def'] >>> for i in x: ... print(i) ... abc xyz def
Here are some examples of this type of “while loop”:
while <expr>: <statement(s)>
Here is a representative example:
>>> x = 4 >>> while x > 0: ... x -= 1 ... print(x) ... 3 2 1 0
A function in Python is a named code block that performs actions and, if necessary, computes the result before returning it to the calling code. To describe a function, use the following syntax:
def function_name(arg1, arg2, ..., argN): # Do something with arg1, arg2, ..., argN return return_value
The function header is started with the def keyword. Then you’ll need the function’s name and a list of arguments enclosed in parentheses. Note that the arguments lists is optional, but the parentheses are required.
The last step is to define the function’s code block, which will start one level to the right of the indentation. The return statement is also optional in this case, and you can use it if you need to give a return_value to the caller code. You must call a function in order to use it.
function_name(arg1, arg2, ..., argN)
Although some functions when called, do not require the arguments, the parentheses are still required. If you forget them, you’ll be referring to the function as a function object rather than calling it.
In this blog, we learn the basic fundamentals of how to use python as a beginner. If you are a student and need a python assignment solution, please contact us or comment below. We will provide you the best python programming help service at the most affordable price.