PythonType Casting

Type Casting in Python

Type casting (also called type conversion) is the process of converting one data type into another.

In Python, type casting can be:

  • Implicit (automatic) — handled by Python itself when no data loss will occur.
  • Explicit (manual) — done by the programmer using type conversion functions.

Common Type Conversion Functions

FunctionDescription
int(x)Converts to integer
float(x)Converts to float
str(x)Converts to string
bool(x)Converts to boolean
list(x)Converts to list
tuple(x)Converts to tuple
set(x)Converts to set

Example 1: Integer Conversion (int())

typecasting_int.py
x = 5.8
print(int(x))     # Float to int
 
y = "42"
print(int(y))     # String to int
 
z = True
print(int(z))     # Bool to int
output.txt
5
42
1

Explanation:

  • Converts float to integer (drops decimal).
  • Converts numeric string to integer.
  • Converts boolean: True → 1, False → 0.

Example 2: Float Conversion (float())

typecasting_float.py
x = 7
print(float(x))   # Int to float
 
y = "3.14"
print(float(y))   # String to float
 
z = False
print(float(z))   # Bool to float
output.txt
7.0
3.14
0.0

Explanation:

  • Converts integer to float.
  • Converts numeric string to float.
  • Converts boolean to float.

Example 3: String Conversion (str())

typecasting_str.py
x = 25
print(str(x))     # Int to string
 
y = 8.5
print(str(y))     # Float to string
 
z = None
print(str(z))     # None to string
output.txt
25
8.5
None

Explanation:

  • Converts any object to a string.
  • Useful for concatenation or display.

Example 4: Boolean Conversion (bool())

typecasting_bool.py
print(bool(0))         # Zero → False
print(bool(42))        # Non-zero → True
print(bool(""))        # Empty string → False
print(bool("Hello"))   # Non-empty string → True
output.txt
False
True
False
True

Explanation:

  • 0, empty string, None, empty containers → False.
  • All other values → True.

Example 5: List Conversion (list())

typecasting_list.py
x = "abc"
print(list(x))         # String to list of characters
 
y = (1, 2, 3)
print(list(y))         # Tuple to list
output.txt
['a', 'b', 'c']
[1, 2, 3]

Explanation:

  • Converts iterable (string, tuple) into list.
  • Each element becomes a list item.

Example 6: Tuple Conversion (tuple())

typecasting_tuple.py
x = [10, 20, 30]
print(tuple(x))        # List to tuple
 
y = "xyz"
print(tuple(y))        # String to tuple
output.txt
(10, 20, 30)
('x', 'y', 'z')

Explanation:

  • Converts iterable into tuple.

Example 7: Set Conversion (set())

typecasting_set.py
x = [1, 2, 2, 3]
print(set(x))          # List to set (removes duplicates)
 
y = "aab"
print(set(y))          # String to set of unique characters
output.txt
{1, 2, 3}
{'a', 'b'}

Explanation:

  • Converts iterable into set.
  • Removes duplicate values.

Implicit Type Casting

Python also automatically converts types where possible.

implicit_typecasting.py
x = 5
y = 2.5
result = x + y
print(result)
print(type(result))
output.txt
7.5
<class 'float'>

Explanation:

  • Python promotes int to float automatically to avoid data loss.

Summary

  • Explicit Type Casting is done using functions like int(), float(), str(), etc.
  • Implicit Type Casting is performed automatically when safe.
  • Type casting is very useful for user input, arithmetic, string formatting, and data processing.
OutputArithmetic Operators