Python chr() Function: Convert Unicode Code Points to Characters (With Examples)

Unicode is a character encoding standard that assigns a unique code point (integer value) to every character in various writing systems, including letters, symbols, and emojis. Python provides a built-in function called chr() that allows you to convert Unicode code points into their corresponding characters. This function is particularly useful when you’re working with Unicode data and need to display characters rather than their integer representations.

In this tutorial, we will explore the chr() function in depth, covering its syntax, usage, and providing several examples to illustrate its practical applications.

Table of Contents

• Introduction to Unicode and chr()
• Syntax of the chr() Function
• Using chr() with Unicode Code Points
• Examples of chr() in Action
• Example 1: Basic Usage
• Example 2: Creating Strings from Code Points
• Handling Invalid Unicode Code Points
• Conclusion

Introduction to Unicode and chr()

Unicode is a standardized character encoding system that assigns unique numerical values to characters from different languages and scripts. This system allows computers to represent and manipulate text from various writing systems, ensuring consistent and accurate character representation across different platforms and programming languages.

The chr() function in Python is used to convert an integer Unicode code point into its corresponding character. This is especially useful when dealing with textual data that includes characters from multiple languages or when you need to create human-readable output from raw Unicode code points.

Syntax of the chr() Function

The syntax of the chr() function is quite simple:

chr(i)

Here, i is the integer Unicode code point that you want to convert into a character.

Using chr() with Unicode Code Points

The chr() function takes an integer argument, which represents a Unicode code point, and returns a string containing the corresponding character. It’s important to note that the Unicode code point provided to the chr() function must be within the valid Unicode code point range, which is 0 to 0x10FFFF.

Let’s take a look at a few examples to understand how the chr() function works.

Examples of chr() in Action

Example 1: Basic Usage

# Using the chr() function to convert Unicode code points to characters
code_point_1 = 65  # Unicode code point for 'A'
code_point_2 = 8364  # Unicode code point for Euro symbol

char_1 = chr(code_point_1)
char_2 = chr(code_point_2)

print("Character 1:", char_1)  # Output: Character 1: A
print("Character 2:", char_2)  # Output: Character 2: €

In this example, we use the chr() function to convert Unicode code points 65 and 8364 into characters ‘A’ and ‘€’, respectively.

Example 2: Creating Strings from Code Points

# Creating a string from a list of Unicode code points using chr()
code_points = [72, 101, 108, 108, 111]  # Unicode code points for 'Hello'

# Using list comprehension and chr() to convert code points to characters
string_from_code_points = ''.join(chr(code) for code in code_points)

print("String from code points:", string_from_code_points)  # Output: String from code points: Hello

In this example, we have a list of Unicode code points representing the characters of the word ‘Hello’. We use a list comprehension along with the chr() function to convert these code points into characters and then join them to form the string ‘Hello’.

Handling Invalid Unicode Code Points

It’s important to note that the chr() function expects a valid Unicode code point as input. If you provide an integer that falls outside the valid Unicode code point range, you will encounter a ValueError. For example:

invalid_code_point = 1500000

try:
    invalid_char = chr(invalid_code_point)
except ValueError as e:
    print("Error:", e)  # Output: Error: chr() arg not in range(0x110000)

In this case, the provided invalid_code_point is outside the valid range, resulting in a ValueError.

Conclusion

The chr() function in Python is a handy tool for converting Unicode code points into their corresponding characters. It allows you to work with Unicode data more effectively and produce human-readable output. Whether you’re dealing with multilingual text or simply need to display Unicode characters, the chr() function simplifies the process of converting code points to characters. Just remember to ensure that the code points you provide are within the valid Unicode range to avoid errors.