Type Conversion in Python

Type conversion in Python is the process of changing a value from one data type to another.

• Helps ensure correct operations and calculations.
• Examples include converting an integer to a float or a numeric string to an integer.
• Python supports two types of type conversion: Implicit Conversion and Explicit Conversion.

Implicit Type Conversion

Implicit conversion in Python happens automatically when different data types are used together in an expression.

• Python converts a smaller data type to a larger one when needed.
• Commonly occurs when integers and floats are combined.
• Conversion happens at runtime to keep results accurate.

x: <class 'int'>
y: <class 'float'>
z = 20.6
z : <class 'float'>

In the above example:

• "x" is an integer and "y" is a float.
• During "z = x + y", Python implicitly converts x to a float to avoid data loss.
• As a result, "z" becomes a float with the value 20.6.

Explicit Type Conversion

Explicit conversion, also called type casting, is when a programmer manually changes a value from one data type to another.

• Done using Python’s built-in functions like int(), float(), and str().
• Gives full control over how data is interpreted or processed.
• Used when automatic conversion is not suitable.

Common type casting functions

• int() converts a value to an integer
• float() converts a value to a floating point number
• str() converts a value to a string
• bool() converts a value to a Boolean (True/False)

100
<class 'int'>

In the above example:

• s is a string with the value "100".
• Using int(s), the string is explicitly converted into an integer.
• This manual conversion is called explicit type conversion, and a becomes the integer 100 with type <class 'int'>.

Examples of Common Type Conversion Functions

Example 1: Converting a binary string

18
10010.0

In the above example:

• int(s, 2) interprets the binary string '10010' as the integer 18.
• float(s) converts the string to a floating-point number.

Example 2: ASCII, Hexadecimal and Octal Conversion

ASCII of '4': 52
56 in Hex: 0x38
56 in Octal: 0o70

In the above example:

• ord(c) returns the ASCII code of the character '4'.
• hex() and oct() convert the integer 56 to its hexadecimal and octal representations, respectively.

Example 3: String to Tuple, Set and List

To tuple: ('g', 'e', 'e', 'k', 's')
To set: {'e', 'g', 'k', 's'}
To list: ['g', 'e', 'e', 'k', 's']

In the above example:

• tuple(s) keeps all characters including duplicates in order.
• set(s) removes duplicates and returns an unordered collection.
• list(s) returns a list of characters from the string.

Example 4: Other Conversions – Complex, String, Dictionary

To complex: (1+2j)
To string: 1
To dict: {'a': 1, 'f': 2, 'g': 3}

In the above example:

• complex(1, 2) creates a complex number with real part 1 and imaginary part 2.
• str(a) converts the integer 1 to the string "1".
• dict(tup) creates a dictionary from a sequence of key-value tuples.