Python format() combined with join and data conversion

Question

This Python code gives exactly what I want:

a_hex_str = ':'.join('%02x' % b for b in a_bytes)

which is a string of the byte values in the byte array a_bytes printed in hex with a colon between each value.

I have been going mad trying to get the same output using the new format() function in place of the old % but all my attempts give errors.

I would be very grateful for assistance.

score 0 · Answer 1 · answered Sep 28 '19 at 13:18

0

a_hex_str = ':'.join('{}02x'.format(b) for b in a_bytes)

Try this line hopefully it will work.

answered Sep 28 '19 at 13:18

Vashdev Heerani

No, it doesn't. It prints the bytes in decimal and puts 02x after each. I want to print the bytes in hex. – simonc8 Sep 28 '19 at 13:27

score 0 · Answer 2 · answered Sep 28 '19 at 16:23

a_hex_str = ':'.join('{:02x}'.format(b) for b in a_bytes)

I didn't realise I needed the colon inside the curly braces, otherwise it gives an out of range error.

2 Answers2