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Starting as a Freshman in Python Programming

Starting as a Freshman in Python Programming

How do I get started learning Python Programming?

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Joshua Obikunle
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Python is a widely used computer programming language for creating software and websites, automating processes, and conducting data analysis. A general-purpose language is Python. It is not specialized to any one type of issue and can be utilized to construct a wide range of programs. Since its initial release in 1991, it has grown to rank among the most widely used programming languages worldwide.

Python's readability is one of its important characteristics because the language is meant to be straightforward to learn. Its grammar is similar to that of English, making it simpler for beginners to comprehend and create code. Furthermore, Python has a sizable and helpful community that provides a wealth of tools and assistance to get you started.

Getting Started with Python

Let's dive into the exciting world of Python programming. You'll learn how to install Python on your computer, understand its syntax and structure and learn how to write your first Python program

Install Python

The first step is to install Python on your computer. You can download the latest version of Python from the official website or directly from here.

Run a Python Interpreter

Once you have installed Python, you can run the Python interpreter to start using the language. The interpreter is an environment where you can run your Python code line by line.

To run a Python interpreter, you can use one of the following methods:

  • Running Python Interpreter from Command Line Interface (CLI)

If you're using a computer with a command-line interface (such as Windows Command Prompt or a Linux terminal), you can simply type "python" in the terminal to start the interpreter.

$ python
Python 3.x.x
Type "help", "copyright", "credits" or "license" for more information.
>>>

  • Running Python Interpreter from IDLE

IDLE is the built-in Python Integrated Development Environment (IDE) that comes with the Python installation. To start IDLE, simply search for IDLE in your start menu (on Windows) or launch

$ python
Python 3.x.x
Type "help", "copyright", "credits" or "license" for more information.
>>>

Note that the "\>>>" prompt in the interpreter is where you can enter your Python code. You can type in expressions, run code snippets, and see the results immediately. The interpreter will continue to run until you exit it by typing exit() or quit().

Write Your First Python Program

To get started, you can write a simple "Hello, World!" program in Python. Here's an example:

print("Hello World!")
'Hello World!'

Your output would come out like this: 'Hello, World!'

As you can see, eazzie pezzie!

Variables and Data Types

In ordinary terms, a "variable" is a quality that could alter depending on the circumstances surrounding an issue or experiment. Generally, a variable is denoted by a single letter. The available symbols for variables most frequently used are the letters x, y, and z.

While in Python, it can be used to store data. A variable is a term used to identify a value. Python has several built-in data types, including texts, integers, and floating-point numbers.

  • Variables

It is a named reference to a value, as was already stated. The equal sign (=) is used to assign values to variables. For example;

x = 25

Here, a variable called "x" has been created and given the value 25. Moreover, you can give variable values for many kinds of data, including text, floating-point numbers, and others.

name = "Josh Obi"
gpa = 3.5

  • Data Types

    Python values can be of various data kinds, including texts, floating-point numbers, integers, and more. Python's standard data types include:

A string (str) is a collection of characters, such as "Hello, World!" or "Josh Obi."

An integer (int) is a whole number, such as 1, 2, or 3.

And a floating-point number (float) is a number that has a decimal point, such as 1.5 or 2.7.

You can check the type of a value in Python using the type() function.

x = 10
print(type(x))  # Output: <class 'int'>

y = 3.14
print(type(y))  # Output: <class 'float'>

z = "Hello, World!"
print(type(z))  # Output: <class 'str'>

Operators and Expressions

Operators are an integral part of the Python programming language. They are used to perform various mathematical or logical operations on operands, which are the values that operators act on.

Here is an example:

a = 10
b = 20
print(a + b)

In Python, operators are represented by special symbols that are designed to perform specific functions. Some of the commonly used operators in Python include arithmetic operators such as addition, subtraction, multiplication, and division; comparison operators such as greater than, less than, and equal to; logical operators such as AND, OR, and NOT; and assignment operators such as equals (=) and plus-equals (+=).

Expressions that carry out various operations on variables and values can be built using these operators. For instance, you can combine two numbers using the addition operator (+), multiply two numbers using the multiplication operator (*), or compare two values by using the equality operator (==). You can build complicated expressions that can carry out complex calculations or make logical choices based on certain criteria by combining these operators with variables and values.

>>> a = 10
>>> b = 20
>>> a == b
False

>>> a != b
True
>>> a <= b
True
>>> a >= b
False

>>> a = 30
>>> b = 30
>>> a == b
True

>>> a <= b
True
>>> a >= b
True

Ultimately, knowing how operators function is a crucial part of learning Python since it allows you to meaningfully change and deal with data. With enough practice, you will be capable of learning how to use operators to perform various operations and construct intricate expressions that will aid you in solving real-world problems.

Control Flow

The sequence in which a Python program carries out statements is referred to as "control flow." Conditional statements, loops, and function calls are just a few of the tools offered by Python for managing program flow.

With conditional statements, you may decide which blocks of code to run based on whether a certain condition is true or not. If, else, and elif constructs are used in Python to implement conditional statements. For instance:

# Program to check if a number is positive or negative
num = 5

if num >= 0:
    print("The number is positive")
else:
    print("The number is negative")

We can also nest the if-else statement:

# Program to check if a number is positive, negative or zero
num = 0

if num > 0:
    print("The number is positive")
elif num == 0:
    print("The number is zero")
else:
    print("The number is negative")

We also have what we refer to as "loops."

Loops are used to repeatedly run a block of code, either for a predetermined number of iterations or until a predetermined condition is satisfied. FOR loops and WHILE loops are the two types of loops that Python offers. A for loop is used to repeatedly iterate over a list or string of values. While a specific condition is true, a while loop is used to repeatedly run a block of code.

Check this:

# A 'for' loop
# Program to print numbers from 1 to 5
for i in range(1, 6):
    print(i)

# A 'while' loop
# Program to print even numbers between 1 and 10
num = 1

while num <= 10:
    if num % 2 == 0:
        print(num)
    num += 1

Functions

A chunk of code called a "function" in programming is used to carry out a particular purpose. A huge program could be divided into smaller, more manageable sections with the help of functions, which can make it simpler to debug and maintain. Also, they can be reused in many areas of your application, which can assist you in reducing time and writing less code overall.

Here is an illustration of a straightforward Python function:

def greet(name):
    print("Hello, " + name + "!")

greet("John")

The function in this example is called greet and only accepts the argument name. "Hello, John!" is printed to the console when the function is called with the input "John."

The many components of this function are broken down as follows:

  1. In Python, a function is defined with the def keyword. The name of the function (greet) and any parameters it requires are listed after this (in this case, name).

  2. Behind the def statement, the body of the function is indented. In this instance, the function merely uses the print command to output a message to the console.

  3. When the greet function is called with the input "John," the message "Hello, John!" is printed to the console and the welcome function is run.

Moreover, functions can return results, which is helpful if you need to do a calculation and use the outcome in another section of your program. Here is an illustration of a function that returns a number's square:

def square(num):
    return num * num

result = square(5)
print(result)

The square function in this example returns the square of the single input (num). The function returns the number 25 when it is invoked with the argument 5, and the variable result is then given that value. The value of the result is finally sent to the console using the print command.

These are just a few uses for functions in Python, but they are crucial to the language and are frequently used in programming to produce reusable and maintainable code.

Modules

Python has a sizable library of pre-written code that you can use to enhance the functionality of your programs. You can import these libraries, which are divided up into modules, into your program to use its features.

A file containing Python definitions and statements is known as a "module" in the language. The module name with the.py extension is used as the file name. You can group your code logically using modules, which can make it simpler to manage and reuse code across various parts of your program.

Here is an illustration of a straightforward Python module:

  • Create a new file called my_module.py.

  • Add the following code to the file:

def greet(name):
    print("Hello, " + name + "!")
  • Save the file

Once a module has been created, it can now be used in another area of your program. Using the greet function from the my_module module, for instance, looks like this:

  1. Create a new file called my_program.py.

  2. Add the following code to the file:

     import my_module

 my_module.greet("John")

  3. Save file

This example imports the my_module module using the import statement. This enables the greet function in the running program. "Hello, John!" is printed to the console when the greet function is called with the argument "John."

Additionally, you can use the from keyword to import particular variables or functions from a module.

Here's an example:

from my_module import greet

greet("Jane")

We can see that only the greet function was imported from the my_module module. It enables you to use the greet function without first prefixing it with the name of the module in your program.

Python's modules are a key component and are frequently used in programming to organize code and increase its reusability. Python also comes with a ton of built-in modules, like the math module, which offers a wide range of mathematical operations that can be incorporated into your programs.

Conclusion

In conclusion, Python is a popular and versatile programming language that is strong and simple to learn. Python is a fantastic choice for your next project, regardless of whether you are a newbie or an experienced programmer.

I'll see you in the next post.

I hope you enjoyed this piece. To learn more, please like, comment, and share. Thank you!

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