Strings and Number Systems

Understanding the Relationship

While strings and number systems might seem unrelated at first, they are interconnected in Python through data type conversions.

Strings are sequences of characters, representing textual information. They can contain numbers, but they are treated as characters, not numerical values.

Number systems are ways to represent numerical values. Python primarily supports the decimal (base 10) system, but it also allows for binary (base 2), octal (base 8), and hexadecimal (base 16) representations.

Conversion Between Strings and Numbers

Python provides built-in functions to convert between strings and numeric data types:

1. Converting Strings to Numbers:

·         int(): Converts a string to an integer. The string must represent a whole number.

·         float(): Converts a string to a floating-point number. The string can contain a decimal point.

·         complex(): Converts a string to a complex number. The string must be in the form real+imaginaryj.

Python

string_number = "42"

integer_value = int(string_number)

print(integer_value)  # Output: 42

float_value = float("3.14")

print(float_value)  # Output: 3.14

complex_value = complex("2+3j")

print(complex_value)  # Output: (2+3j)

2. Converting Numbers to Strings:

·         str(): Converts a number to a string.

Python

number = 42

string_value = str(number)

print(string_value)  # Output: "42"

Number Systems in Python

Python supports various number systems through string representations:

·         Binary: Preceded by 0b or 0B.

Python

binary_number = 0b1010  # Equivalent to decimal 10

·         Octal: Preceded by 0o or 0O.

Python

octal_number = 0o75  # Equivalent to decimal 61

·         Hexadecimal: Preceded by 0x or 0X.

Python

hexadecimal_number = 0xFF  # Equivalent to decimal 255

Converting Between Number Systems

You can convert between different number systems using built-in functions:

·         bin(): Converts an integer to a binary string.

·         oct(): Converts an integer to an octal string.

·         hex(): Converts an integer to a hexadecimal string.

Python

decimal_number = 42

binary_string = bin(decimal_number)  # Output: '0b101010'

octal_string = oct(decimal_number)  # Output: '0o52'

hexadecimal_string = hex(decimal_number)  # Output: '0x2a'

By understanding the relationship between strings and number systems, you can effectively manipulate and convert data in your Python programs.