Python int to hexadecimal string

Python hex()

Summary: in this tutorial, you’ll learn how to use the Python hex() function to convert an integer number to a lowercase hexadecimal string prefixed with 0x .

Introduction to the Python hex() function

The hex() function accepts an integer and converts it to a lowercase hexadecimal string prefixed with 0x.

Here’s the syntax of the hex() function:

The following example uses the hex() function to convert x from an integer (10) to a lowercase hexadecimal string prefixed with 0x :

x = 10 result = hex(10) print(result) # 👉 0xa print(type(result)) # 👉 Code language: PHP (php)

If x is not an integer, it needs to have an __index__() that returns an integer. For example:

class MyClass: def __init__(self, value): self.value = value def __index__(self): return self.value result = hex(MyClass(10)) print(result) # 👉 0xa

• First, define the MyClass class with a value attribute.
• Second, initialize the value in the __init__() method.
• Third, implement the __index__() method that returns the value.
• Finally, create a new instance of MyClass and pass it to the hex() function.

Another way to convert an integer to an uppercase or lower hexadecimal string is to use f-strings with a format. For example:

a = 10 h1 = f'' print(h1) # 👉 0xa h2 = f'' print(h2) # 👉 a h3 = f'' print(h3) # 👉 0XA h3 = f'' print(h3) # 👉 ACode language: PHP (php)

Summary

• Use the Python hex() function to convert an integer to a lowercase hexadecimal string prefixed with 0x .

Источник

Python – Convert Integer to Hexadecimal

In this tutorial, we will look at how to convert an integer to hexadecimal in Python with the help of some examples.

How to convert integer to hexadecimal in Python?

You can use the Python built-in hex() function to convert an integer to its hexadecimal form in Python. Pass the integer as an argument to the function. The following is the syntax –

# convert int i to hexadecimal hex(i)

It returns the integer’s representation in the hexadecimal number system (base 16) as a lowercase string prefixed with ‘0x’ .

Examples

Let’s look at some examples of using the above function to convert int to hex.

Positive integer to hexadecimal

Pass the integer as an argument to hex function.

# int variable num = 15 # int to hex num_hex = hex(num) # display hex and type print(num_hex) print(type(num_hex))

You can see that we get the hexadecimal representing the integer as a lowercase string with ‘0x’ prefix.

If you do not want the prefix, you can use the string slice operation to remove the prefix from the returned hex string.

Negative integer to hexadecimal

Let’s now apply the same function to a negative integer.

# int variable num = -15 # int to hex num_hex = hex(num) # display hex and type print(num_hex) print(type(num_hex))

We get its hexadecimal string.

Integer to uppercase hexadecimal string

Alternatively, you can use the Python built-in format() function to convert an integer to its hexadecimal form. You can customize the format of the returned string.

For example, to convert an integer to an uppercase hexadecimal string, use the format string ‘#X’ or ‘X’ .

# int variable num = 15 # int to hex num_hex = format(num, '#X') # display hex and type print(num_hex) print(type(num_hex))

We get the hexadecimal for the integer as an uppercase string.

With the format() function you can customize the returned hexadecimal string – with or without the prefix, uppercase or lowercase, etc.

# int variable num = 15 # int to hex print(f"Lowercase with prefix: ") print(f"Lowercase without prefix: ") print(f"Uppercase with prefix: ") print(f"Uppercase without prefix: ")

Lowercase with prefix: 0xf Lowercase without prefix: f Uppercase with prefix: 0XF Uppercase without prefix: F

You might also be interested in –

Subscribe to our newsletter for more informative guides and tutorials.
We do not spam and you can opt out any time.

Author

Piyush is a data professional passionate about using data to understand things better and make informed decisions. He has experience working as a Data Scientist in the consulting domain and holds an engineering degree from IIT Roorkee. His hobbies include watching cricket, reading, and working on side projects. View all posts

Data Science Parichay is an educational website offering easy-to-understand tutorials on topics in Data Science with the help of clear and fun examples.

Career Guides

• Start Your Path —
• Data Scientist
• Data Analyst
• Data Engineer
• Machine Learning Engineer
• Statistician
• Data Architect
• Software Developer

Useful Resources

This website uses cookies to improve your experience. We’ll assume you’re okay with this, but you can opt-out if you wish.

Privacy Overview

This website uses cookies to improve your experience while you navigate through the website. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may affect your browsing experience.

Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.

Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. It is mandatory to procure user consent prior to running these cookies on your website.

Источник

Convert integer to hex in Python

In Python I want to tranform the integer 3892 into a hexcode with the given format and the result \x00\x00\x0F\x34 . How can this be achieved?

Hmmm, so you want code based on a hope and prayer, fine. When you say «hexcode with the given format» do you mean literally a string of bytes representing the 32-bit value 0x0f34 on a big-endian machine, or do you mean literally the character string «\\x00\\x00\\x0F\\x34» ?

In other words, do you need a 16 character string (textual representation) or 4 bytes (binary representation)?

3 Answers 3

You are converting to a binary representation of the number, not so much a hex representation (although Python will display the bytes as hex). Use the struct module for such conversions.

>>> struct.pack('>I', 3892) '\x00\x00\x0f4' >>> struct.pack('>I', 4314) '\x00\x00\x10\xda' 

Note that the ASCII code for ‘4’ is 0x34, python only displays bytes with a \x escape if it is a non-printable character. Because 0x34 is printable, python outputs that as 4 instead.

‘>’ in the formatting code above means ‘big endian’ and ‘I’ is an unsigned int conversion (4 bytes).

@martineau: I address that in my answer; python displays ‘4’ because that is the ASCII character at code position 0x34. Thus, the last character in the byte sequence is \x34 but because it is printable it is not displayed as a hex escape.

Ahhh, I get what you meant by the statement in your answer now, thanks. It’s unclear if the OP wants this or what @cdarke’s answer produces, but suspect it’s probably the former, so will have to add my own +1.

import re print re.sub(r'([0-9A-F])',r'\\x\1','%08X' % 3892) 

wow! thats it — really cool. Thanks a lot. @cdarke for the sake of my mediocre regex-skills: could you give me a short explenation of your regex?

This produces a 16-character string with literal backslash, literal x and literal digits. ‘%08X’ produces the hexadecimal digits, and the regular expression inserts a literal \x every two digits. My solution produces 4 bytes, which contain your number as an unsigned C long value. You need to figure out what format you need to write to your file; if it is a binary format my bet is on my answer. 🙂

Sorry for the delay, I have been travelling. The RE is as follows (in addition to @Martijn Pieters correct explaination): ([0-9A-F]<2>) looks for exactly 2 hexadecimal digits. The parentheses () capture what we matched, and are represented in the replacement string as \1 (called a back-reference). \\x prefixes the captured two characters with \x . Would be nice if you accepted my solution if you are happy with it, but I agree with others that your question is a little ambiguous.

Источник

Format ints into string of hex

I need to create a string of hex digits from a list of random integers (0-255). Each hex digit should be represented by two characters: 5 — «05», 16 — «10», etc. Example:

Input: [0,1,2,3,127,200,255], Output: 000102037fc8ff 

#!/usr/bin/env python def format_me(nums): result = "" for i in nums: if i  

>>> numbers = [1, 15, 255] >>> ''.join(''.format(a) for a in numbers) '010FFF' 

 [''.format(i) for i in [1, 15, 255]] 

>>> str(bytearray([0,1,2,3,127,200,255])).encode('hex') '000102037fc8ff' 

>>> bytearray([0,1,2,3,127,200,255]).hex() '000102037fc8ff' 

a = [0,1,2,3,127,200,255] print binascii.hexlify(bytes(bytearray(a))) 

binascii.hexlify(memoryview(bytearray(a))) 

>>> numbers = [1, 15, 255] >>> fmt = '' * len(numbers) >>> fmt.format(*numbers) '010FFF' 

a = [0,1,2,3,127,200,255] print str.join("", ("%02x" % i for i in a))