Belajar Python Dasar - #01 Variabel

Introduction

This tutorial is designed for beginners who want to learn the basics of Python programming, focusing specifically on the concept of variables. Understanding variables is crucial as they are fundamental components of any programming language. This guide will walk you through what variables are, how to declare them, the rules for naming variables, and practical examples to help solidify your understanding.

Step 1: Understanding Variables

• Definition: A variable is a storage location identified by a name that can hold data. It allows you to store and manipulate values in your program.
• Real-world analogy: Think of a variable as a box with a label. The label is the variable name, and the contents of the box are the data stored in that variable.

Step 2: Declaring Variable Types

• Dynamic typing: Python is dynamically typed, meaning you don’t need to explicitly declare the type of a variable. The type is inferred from the value assigned to it.
• Common types:
  • Integer: int
  • Floating-point: float
  • String: str
  • Boolean: bool

Example of Variable Declaration

x = 10           # An integer
y = 3.14        # A floating-point number
name = "Alice"  # A string
is_student = True  # A boolean

Step 3: Naming Rules for Variables

• Must start with a letter or underscore: The name cannot begin with a number.
• Can contain letters, numbers, and underscores: Avoid using spaces or special characters.
• Case-sensitive: variable and Variable are considered different.
• Avoid using Python keywords: Keywords like if, for, while, etc., cannot be used as variable names.

Step 4: Using Google Colab

• Introduction: Google Colab is an online platform that allows you to write and execute Python code in a web-based environment.
• Getting started:
  • Open your browser and navigate to Google Colab.
  • Create a new notebook to start coding.

Step 5: Practical Examples of Creating Variables

1. Single Variable Creation:

   • Open Google Colab.
   • In a new cell, type the following code and run it:

   age = 25
   print(age)
   

   • This code declares a variable age and prints its value.

2. Multiple Variables Creation:

   • To declare multiple variables at once, use commas:

   a, b, c = 1, 2, 3
   print(a, b, c)
   

Step 6: Understanding Variable Value Changes

• Reassigning Values: You can change the value of a variable at any time.

x = 5
print(x)  # Output: 5
x = 10
print(x)  # Output: 10

Step 7: Checking Variable Types

• Use the built-in type() function to check the type of a variable.

value = 42
print(type(value))  # Output: <class 'int'>

Conclusion

In this tutorial, you learned about the fundamental concept of variables in Python, including how to declare them, the rules for naming, and how to check their types. You also practiced creating variables using Google Colab. As you progress in your Python journey, try creating more complex variable types and explore how they can be used in different programming scenarios. Next, consider learning about data structures like lists and dictionaries to further expand your programming skills.