Converting an integer to a hexadecimal string in Ruby

Question

Is there a built in way to convert an integer in Ruby into its hexadecimal equivalent.

The opposite of

"0A".to_i(16)
=>10

or

"0A".hex
=>10

I know how to roll my own, but it's probably more efficient to use a built in ruby function

Answer 1

How about:

i = 20

"%x" % i

Answer 2

how about this:

10.to_s(16) #=> "a"
255.to_s(16) #=> "ff"

Documented here [edit - my bad I copy pasted my link too fast and put the String one instead of the Fixnum one]