start-coding-with

PYTHON

Where do I start?

Whether you're a tech enthusiast, a career changer, or someone simply curious about the art of programming, taking your first steps can be both thrilling and a little overwhelming. In this blog post, we'll guide you through the basics of starting your coding journey with Python, a versatile and beginner-friendly programming language.

Beginners Guide Python

Setting up the environment

Let's go easy and simple...

Before we start coding, we need to set up our coding environment. Installing Python on a computer is the first step. Additionally, choosing an Integrated Development Environment (IDE) is crucial for a seamless coding experience. IDEs like VSCode or PyCharm provide tools to write, test, and debug your code efficiently.

Setting up your coding environment is like decorating a room – install Python as the foundation, choose an IDE for comfort and efficiency, and create a space where your coding ideas can come to life.

Get compatible python from python.org

- Install Python: A step-by-step guide to downloading and installing Python on your computer.

(Note to click on [] Add python to path 👉

- Choosing an IDE (Integrated Development Environment): Explore beginner-friendly IDEs like VSCode, PyCharm, or Jupyter for a smooth coding experience.

Once you have successfully installed python you can type command "python --version" on your command line or terminal depending upon your OS. It should show which version of python installed.

And if the python is linked on the path then typing python on the command line would start the python shell or interpreter as we can start typing and run code line by line.

Your first hello world

python on file...

Code on code editor 👆This is VSCODE

python ./filename.py

Run your code on cmd or terminal

Datatypes

Like Real numbers, Whole numbers, Integers , Decimal Numbers, Rational and irrational numbers in maths.

Integer:

my_integer = 42

Float (Floating-point number):

my_float = 3.14

String:

my_string = "Hello, Python!"

Boolean:

is_true = True

is_false = False

List:

my_list = [1, 2, 3, 4, 5]

Tuple:

my_tuple = (10, 20, 30)

Set:

my_set = {1, 2, 3, 4, 5}

Dictionary:

my_dict = {'name': 'John', 'age': 25, 'city': 'New York'}

None Type:

no_value = None

Variables

In coding, think of variables as labeled boxes where you keep different types of information. Just like you sort your toys into different boxes, learning about data types in Python (like numbers, words, and true/false values) helps you organize and work with your information in a super smart way. It's like learning the ABCs before writing stories – the basics that set you up for cooler, more complex stuff in the coding world!

Examples of variables in python

# Good variable names

total_count = 100

user_name = "JohnDoe"

# Avoid using reserved words

# class = "Python" # This will raise an error

# Dynamic typing

x = 10

x = "Hello"

Follow these rules for clean and readable Python variable names!

Naming Conventions: Use letters, numbers, and underscores; no spaces; case-sensitive.

Reserved Keywords: Avoid using Python reserved words as variable names.

Descriptive Names: Choose meaningful names for clarity (e.g., total_count).

No Spaces or Special Characters: Use underscores for multi-word names.

Dynamic Typing: No need to declare variable types explicitly.

Reassignment: Change a variable's value by assigning a new one.

Underscores for Clarity: Use snake_case for multi-word names.

Operators in python

Arithmetic Operators

x = 5

y = 2

sum_result = x + y

difference_result = x - y

product_result = x * y

division_result = x / y

Assignment Operators

x = 5

y = 2

x += y # Equivalent to x = x + y

Comparison Operators

x = 5

y = 2

is_equal = x == y

is_greater = x > y

Logical Operators

x = True

y = False

logical_and = x and y

logical_or = x or y

logical_not = not x

Identity Operators

x = 5

y = 2

sum_result = x + y

difference_result = x - y

product_result = x * y

division_result = x / y

Membership Operators

x = 5

y = 2

x += y # Equivalent to x = x + y

Control Flow: Making Decisions and Repeating Actions

Control flow, like using if statements for decisions and loops for repetition, guides your program's flow. There are two main types:

Conditional Statements (if, elif, else)

The if statementif condition: statement1 statement2

age = 18if age >= 18: print("You can vote!")else: print("Sorry, you're too young to vote.")

age = 18if age >= 18: print("You can vote!")elif age >= 16: print("Almost there! In a couple of years.")else: print("Sorry, you're too young to vote.")

Indentation: Python relies heavily on indentation (white space before a statement) to define code structure. This makes Python code easy to read and understand.

a_number = 34if a_number % 2 == 0: print("We're inside an if block") print('The given number {} is even.'.format(a_number))We're inside an if blockThe given number 34 is even.

Loops (for and while)

A for loop is used for iteration or looping over sequences, i.e., lists, tuples, dictionaries, strings, and ranges. For loops have the following syntax

Example of a for loop

Looping over a list

days = ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday']
for day in days: print(day)

Looping over a string

for char in 'Sunday': print(char)

Looping over a tuple

for fruit in ['Orange', 'Mango', 'Pineapple']: print("Here's a fruit:", fruit)

Looping over a dictionary

person = {    'name': 'Jane Smith',    'sex': 'Female',    'age': 28,    'married': False}
for key in person:    print("Key:", key, ",", "Value:", person[key])

for value in person.values():    print(value)

for key_value_pair in person.items():    print(key_value_pair)

for key, value in person.items():    print("Key:", key, ",", "Value:", value)

Creating and using functions

A function is a reusable set of instructions that takes one or more inputs, performs some operations, and often returns an output. Python contains many in-built functions like print, len, id, type, input, etc., and provides the ability to define new ones.

today = "Saturday"

print("Today is", today)

You can define a new function using the def keyword.

def say_hello():

print('Hello there!')

print('How are you?')

say_hello()

Function arguments

Functions can accept zero or more values as inputs (also known as arguments or parameters). Arguments help us write flexible functions that can perform the same operations on different values. Further, functions can return a result that can be stored in a variable or used in other expressions.

Parameter

A parameter is a variable that is used in the function definition.
It's a placeholder for the actual value that will be passed to the defined function.
Parameters are placed in the function's signature and act as input placeholders.

Argument

An argument is a value that is passed to a function when invoking or calling it.
It is the actual value that is supplied to the function during the function call.
Arguments are provided in the function call and they get assigned to the corresponding parameters.

def filter_even(number_list): # 'number_list' is a parameter

result_list = []

for number in number_list:

if number % 2 == 0:

result_list.append(number)

return result_list

even_list = filter_even([1, 2, 3, 4, 5, 6, 7])# [1, 2, 3, 4, 5, 6, 7] is a parameter

Even_list

def greet(name): # 'name' is a parameter

print(f"Hello, {name}!")

greet("Jerry") # 'Jerry' is the argument passed to the 'name' parameter

What's next......

Required positional arguments
Keyword arguments
*args - **kwargs
variable scope in python
Closures and Decorators

Modules
Error handling
File Handling

Oops and classes

Inheritance
Encapsulation
Polymorphism
Abstraction

Lambda, Map, and filter higher-order function:

start-coding-with

Beginners Guide Python

Code on code editor 👆This is VSCODE

Run your code on cmd or terminal

Integer:

Float (Floating-point number):

String:

Boolean:

List:

Tuple:

Set:

Dictionary:

None Type:

Examples of variables in python

Follow these rules for clean and readable Python variable names!

Naming Conventions: Use letters, numbers, and underscores; no spaces; case-sensitive.

Reserved Keywords: Avoid using Python reserved words as variable names.

Descriptive Names: Choose meaningful names for clarity (e.g., total_count).

No Spaces or Special Characters: Use underscores for multi-word names.

Dynamic Typing: No need to declare variable types explicitly.

Reassignment: Change a variable's value by assigning a new one.

Underscores for Clarity: Use snake_case for multi-word names.

Arithmetic Operators

Assignment Operators

Comparison Operators

Logical Operators

Identity Operators

Membership Operators

Conditional Statements (if, elif, else)

Indentation: Python relies heavily on indentation (white space before a statement) to define code structure. This makes Python code easy to read and understand.

Loops (for and while)

A for loop is used for iteration or looping over sequences, i.e., lists, tuples, dictionaries, strings, and ranges. For loops have the following syntax

Example of a for loop

Looping over a list

Looping over a string

Looping over a tuple

Looping over a dictionary

Creating and using functions

A function is a reusable set of instructions that takes one or more inputs, performs some operations, and often returns an output. Python contains many in-built functions like print, len, id, type, input, etc., and provides the ability to define new ones.

You can define a new function using the def keyword.

Function arguments

Functions can accept zero or more values as inputs (also known as arguments or parameters). Arguments help us write flexible functions that can perform the same operations on different values. Further, functions can return a result that can be stored in a variable or used in other expressions.

Parameter

Argument

What's next......

Oops and classes

More advanced coding tutorials...