Type Conversion in Python

In Python, type conversion (often referred to as type casting) is the process of changing a value from one data type to another.

This is incredibly common in programming. For instance, when you ask a user for input (like their age or birth year), Python receives it as a text string. To do math with it, you must convert that string into a number first!

Python supports two main ways to convert data types:

1. Implicit Type Conversion: Done automatically by the Python interpreter to prevent data loss.
2. Explicit Type Conversion: Done manually by you, the programmer, using built-in functions like int(), float(), or str().

Let us explore both in detail!

Implicit Type Conversion (Automatic)

In safe scenarios, Python will automatically upgrade your data types behind the scenes so you do not lose any valuable details. For example, if you add a whole integer to a decimal float, Python will temporarily treat the integer as a float so the math is 100 percent correct:

The result is: 15.5
The data type of the result is: <class 'float'>

Explicit Type Conversion (Manual)

To change data types manually, you will use Python’s built-in conversion functions. Let us explore the most popular ones!

1. Converting to Integers: int()

The int() function takes a decimal number, a boolean, or a clean text representation of a number and converts it into a whole integer.

Original float: 9.8
Converted integer: 9 (Notice it was not rounded to 10!)

Original string: '123'
Converted integer: 123
Is it math-ready? 123 + 7 = 130

int(True) gives: 1
int(False) gives: 0

2. Converting to Decimals: float()

The float() function converts whole numbers, boolean values, or numeric text strings into floating-point decimal numbers.

Let us see how it works:

From integer 100: 100.0
From string '3.14': 3.14
From boolean True: 1.0

3. Converting to Text: str()

The str() function is highly versatile. It can convert almost any Python object into a string! This is incredibly useful when you want to join text and numbers together.

My name is Alice and I am 30 years old.
F-string style: My name is Alice and I am 30 years old.

4. Converting Collections

You can also convert collections of items (like lists, tuples, and sets) into each other to change their properties:

Tuple converted to List: [1, 2, 3]
String converted to Char List: ['a', 'b', 'c']

List converted to Tuple: (1, 2, 3)

List converted to Set (Duplicates automatically removed): {1, 2, 3, 4}