Python Character Conversion: Understanding the chr() and ord() Functions
Have you ever needed to convert an integer to its corresponding ASCII character or vice versa? If so, then you’ve stumbled upon a common programming task that can be accomplished easily using Python’s built-in character conversion functions: chr() and ord().
In this article, we’ll explore the syntax and usage of these functions, along with some examples and tips for handling errors.
The chr() Function: Converting Integers to Characters
The chr() function takes an integer as its argument and returns the corresponding ASCII character as a string.
This can be used for a variety of purposes such as printing special characters, generating random strings, or encoding messages. Here’s the syntax:
chr(i)
Where i is an integer between 0 and 1,114,111 inclusive, representing the Unicode code point of the desired character. If the integer value falls outside this range, Python will raise a ValueError.
Let’s take a look at an example:
>>> x = 65
>>> chr(x)
'A'
In this example, we’ve assigned the integer value 65 to the variable x and passed it to the chr() function. The function has returned the ASCII character ‘A’ as a string.
It’s important to note that many modern programming tasks involve Unicode characters that may not be ASCII-compatible. For these cases, you may need to consult a Unicode code table to identify the appropriate integer value for your desired character.
Be aware that some Unicode code points may require multiple integer values to be combined or interpreted in a special way.
Valid Range for chr() Function and Handling ValueError
As mentioned earlier the valid range of integers for the chr() function is between 0 and 1,114,111 inclusive. If a value outside this range is passed to the function, it will raise a ValueError with the message “chr() arg not in range(0x110000)”.
It’s important to handle this error appropriately in your code to avoid program crashes or unexpected behaviour. One way to handle this error is to perform some input validation before passing the integer value to the chr() function, such as checking if the value falls within the valid range or wrapping it around if it falls outside the range.
The ord() Function: Converting Characters to Integers
The ord() function, on the other hand, takes a single character as its argument and returns its corresponding ASCII or Unicode integer representation. The syntax is simple:
ord(c)
Where c is a string representing a single character. The function will return an integer value representing the Unicode code point of that character.
Here’s an example:
>>> y = 'B'
>>> ord(y)
66
In this example, we’ve assigned the character ‘B’ to the variable y, and passed it to the ord() function. The function has returned the integer value 66, which represents the Unicode code point of the character ‘B’.
Valid Range for ord() Function and Handling TypeError
Similar to the chr() function, the ord() function has a valid input range. It only accepts a single character – any string with more than one character or an empty string will result in a TypeError.
This error can be handled by validating the input string beforehand and ensuring it meets the requirements of the function.
Conclusion
In conclusion, the chr() and ord() functions are powerful tools in Python’s arsenal for character conversion. With these functions, you can easily switch between integer and string representations of characters, which is useful for a variety of programming tasks.
By understanding their syntax, limitations, and error handling, you can use these functions confidently in your code. Whether you’re working with simple ASCII characters or complex Unicode scripts, Python has you covered.
The ord() Function: Converting Characters to Integers and Handling Errors
In the previous section, we looked at the chr() function for converting integers to characters. In this section, we’ll turn our attention to the ord() function, which does the opposite – it converts characters to integers.
We’ll explore its syntax and usage and also provide examples to illustrate how it works. Additionally, we’ll discuss common errors that programmers might face when using the ord() function and how to handle these errors.
Syntax and Usage of ord()
The ord() function is a built-in function that takes a single argument: a string of length 1. It returns an integer that represents the Unicode code point value of the character.
Here is the syntax of the function:
ord(c)
Where c is a string of length 1. The function returns an integer representing the Unicode code point value of the character.
For example:
>>> c = 'A'
>>> ord(c)
65
In this example, we assigned the character “A” to the variable “c” and used the ord() function to convert it to an integer. The function returned the integer 65, which is the Unicode code point value of the character “A”.
Example of Using ord() with ASCII and Unicode Characters
The ord() function works with ASCII characters as well as Unicode characters. Here are some examples that demonstrate the usage of ord() with both kinds of characters.
>>> c = 'Z'
>>> ord(c)
90
This example shows how to use the ord() function with an ASCII character, “Z”. The function returns the integer 90, which is the Unicode code point value of the character “Z” in the ASCII table.
>>> c = 'é'
>>> ord(c)
233
This example shows how to use the ord() function with a Unicode character, “é”. The function returns the integer 233, which is the Unicode code point value of the character “é” in the Unicode table.
Handling Errors with ord()
When using the ord() function, programmers may encounter a TypeError if they pass in a string that is not of length 1. This can happen if the programmer passes in an empty string or a string with more than one character.
Here is an example:
>>> c = ''
>>> ord(c)
TypeError: ord() expected a character, but string of length 0 found
To avoid this error, programmers can use a conditional statement to check if the string is of length 1 before using the ord() function.
Passing Hexadecimal Data to ord()
Programmers can also pass hexadecimal data to the ord() function by using the built-in int() function and specifying the base of the number. For example:
>>> hex_value = "0x40"
>>> int(hex_value, 16)
64
>>> ord(chr(int(hex_value, 16)))
64
In this example, we assigned the string “0x40” to the variable “hex_value”. We then used the int() function to convert the hexadecimal value to an integer with a base of 16.
We then passed that integer value to the chr() function to get the corresponding character. Finally, we passed that character to the ord() function to get the Unicode code point value of the character.
Summary
In summary, the ord() function is a built-in function in Python that converts a character to its Unicode code point value. It takes a single argument, which is a string of length 1, and returns an integer.
Programmers can use the function with both ASCII and Unicode characters. However, they need to be aware of the possibility of running into a TypeError if they pass in a string that is not of length 1.
Additionally, programmers can pass hexadecimal data to the ord() function by converting the hexadecimal value to an integer with the int() function, and then converting the integer to a character with the chr() function before passing it to the ord() function. In conclusion, Python’s chr() and ord() functions are powerful tools for character conversion that can be used to convert integers to characters and characters to integers respectively.
The chr() function takes an integer as an argument and returns its corresponding ASCII or Unicode character, whereas the ord() function takes a single character and returns its corresponding Unicode code point value. These functions can be used for a variety of purposes, including generating random strings, encoding messages, and printing special characters.
It’s important to handle errors associated with these functions, such as ValueErrors and TypeErrors, appropriately to avoid program crashes or unexpected behavior. By understanding the syntax, limitations, and error handling of the chr() and ord() functions, programmers can use these functions with confidence and improve their Python skills.