Python hex() function, convert decimal to hexadecimal

#python #beginners

The Python hex() function is used to convert decimal to hexadecimal integers, as a string.

You may know binary is base 2 (0,1).
A decimal number is base 10 (0,1,2,3,4,5,6,7,8,9).
A hexadecimal is base 16 (0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F).

They are just different ways of representing the same number in a computer.

For instance

Hexadecimal	Decimal	Binary
A	10	1010
B	11	1011
C	12	1100
10	16	10000
11	17	10001
12	18	10010

Syntax

The syntax of the hex function is:

    hex(x)

Parameter Description:

x decimal integer (base 10)

return value

Returns the hexadecimal number expressed as a string

examples

The following example shows the hex() function in use. It converts the given numbers in decimal into a hexadecimal number:

    >>> hex(255)
    '0xff'
    >>> hex(-42)
    '-0x2a'
    >>> hex(1L)
    '0x1L'
    >>> hex(12)
    '0xc'
    >>> type(hex (12))
    <Class 'str'> # String

Compare these with the above table:

>>> hex(3)
'0x3'
>>> hex(10)
'0xa'
>>> hex(11)
'0xb'
>>> hex(12)
'0xc'
>>>

Computers sometimes put 0x in front, that means the number is a hexadecimal number. For binary it puts 0b in front (try with bin(10)).

You can also do this for numbers in a list:

>>> numbers = [20,10,40,30,60,50,80,70]
>>> for num in numbers:
...     hex(num)
... 
'0x14'
'0xa'
'0x28'
'0x1e'
'0x3c'
'0x32'
'0x50'
'0x46'
>>>

Top comments (4)

Abbi Jo Kitsune (AbbiJKW) • Feb 21

Got me wondering if there were any others apart from 0x and 0b
learned that there's also a rarely used 0o for Octal (base 8) as well as the Hex & Binary notations.

Thought I'd found another until I (finally) discovered 0e4 is just a shorthand for Exponent (Scientific Notation) so will always return Zero, where 2e4 returns float 20,000.0 (2x10x10x10x10), well at least in Python it does. Didn't find any others apart from the three above.