Python Hexadecimal

Question

How to convert decimal to hex in the following format (at least two digits, zero-padded, without an 0x prefix)?

Input: 255 Output:ff

Answer 1

Another solution is:

>>> "".join(list(hex(255))[2:])
'ff'

Probably an archaic answer, but functional.

Answer 2

Use the format() function with a '02x' format.

>>> format(255, '02x')
'ff'
>>> format(2, '02x')
'02'

The 02 part tells format() to use at least 2 digits and to use zeros to pad it to length, x means lower-case hexadecimal.

The Format Specification Mini Language also gives you X for uppercase hex output, and you can prefix the field width with # to include a 0x or 0X prefix (depending on wether you used x or X as the formatter). Just take into account that you need to adjust the field width to allow for those extra 2 characters:

>>> format(255, '02X')
'FF'
>>> format(255, '#04x')
'0xff'
>>> format(255, '#04X')
'0XFF'

Answer 3

I think this is what you want:

>>> def twoDigitHex( number ):
...     return '%02x' % number
... 
>>> twoDigitHex( 2 )
'02'
>>> twoDigitHex( 255 )
'ff'