Python Casting

Casting is the process of converting a variable from one data type to another. In Python, you can cast between different data types using built-in functions. This is particularly useful when you need to perform operations that require a specific data type.

Casting Functions

Python provides several built-in functions for casting between data types:

1. int() – Converts a value to an integer.
2. float() – Converts a value to a floating-point number.
3. str() – Converts a value to a string.

Converting to Integer

Use the int() function to convert a value to an integer. This function can handle strings representing whole numbers, floating-point numbers (by truncating the decimal part), and boolean values.

Explanation of Code:

In the example below, the int() function is used to convert a string "10" to an integer 10, a float 3.14 to an integer 3, and a boolean True to an integer 1.

# Convert string to integer
x = int("10")
print(x)  # Output: 10

# Convert float to integer
y = int(3.14)
print(y)  # Output: 3

# Convert boolean to integer
z = int(True)
print(z)  # Output: 1

# Convert string to integer

x = int("10")

print(x)  # Output: 10

​

# Convert float to integer

y = int(3.14)

print(y)  # Output: 3

​

# Convert boolean to integer

z = int(True)

print(z)  # Output: 1

​

Converting to Float

Use the float() function to convert a value to a floating-point number. This function can handle strings representing numbers and integer values.

Explanation of Code:

In the example above, the float() function is used to convert a string "3.14" to a float 3.14 and an integer 10 to a float 10.0.

# Convert string to float
a = float("3.14")
print(a)  # Output: 3.14

# Convert integer to float
b = float(10)
print(b)  # Output: 10.0

# Convert string to float

a = float("3.14")

print(a)  # Output: 3.14

​

# Convert integer to float

b = float(10)

print(b)  # Output: 10.0

​

Converting to String

Use the str() function to convert a value to a string. This function can handle numbers, booleans, and other data types.

Explanation of Code:

In the example above, the str() function is used to convert an integer 10 to a string "10", a float 3.14 to a string "3.14", and a boolean False to a string "False".

# Convert integer to string
c = str(10)
print(c)  # Output: "10"

# Convert float to string
d = str(3.14)
print(d)  # Output: "3.14"

# Convert boolean to string
e = str(False)
print(e)  # Output: "False"

# Convert integer to string

c = str(10)

print(c)  # Output: "10"

​

# Convert float to string

d = str(3.14)

print(d)  # Output: "3.14"

​

# Convert boolean to string

e = str(False)

print(e)  # Output: "False"

​

Python Casting Example Code

Explanation of Code:

This program uses a predefined input value instead of prompting the user. The input, which is a string, is converted to a float using the float() function. The program performs addition and multiplication operations and prints the results. Finally, the results are converted to strings and printed again.

# Predefined input for testing
input_str = "5"  # Replace this with any number you want to test

# Convert the input string to a float
number = float(input_str)

# Perform calculations
result_add = number + 10
result_multiply = number * 2

# Print the results
print("Addition result:", result_add)
print("Multiplication result:", result_multiply)

# Convert the results to strings and print
print("Addition result as string:", str(result_add))
print("Multiplication result as string:", str(result_multiply))

# Predefined input for testing

input_str = "5"  # Replace this with any number you want to test

​

# Convert the input string to a float

number = float(input_str)

​

# Perform calculations

result_add = number + 10

result_multiply = number * 2

​

# Print the results

print("Addition result:", result_add)

print("Multiplication result:", result_multiply)

​

# Convert the results to strings and print

print("Addition result as string:", str(result_add))

print("Multiplication result as string:", str(result_multiply))

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