How to add "0b" in front of an integer to convert from binary to base 10

Question

I'm trying to convert the integer 1101 in binary to 13 in decimal. I can do:

0b1101.to_s(10) # => 13

How would I take 1101 and add the "0b" to the front? Is that possible?

`0b1101` is just another way to write `13`. In other words: `0b1101` already is `13`. Calling `to_s` will just convert it to a string, i.e. `"13"`. — Stefan, Oct 19 '17 at 20:18

score 2 · Answer 1 · edited Oct 20 '17 at 04:29

2

You don't need to add anything to the string. Just call #to_i on it with the desired base as a parameter:

"1101".to_i(2) # => 13

edited Oct 20 '17 at 04:29

sawa

answered Oct 19 '17 at 20:14

moveson

score 1 · Accepted Answer · edited Oct 20 '17 at 04:28

1

If I get what you're trying to do this should work

Integer("1101", 2) # => 13

edited Oct 20 '17 at 04:28

sawa

answered Oct 19 '17 at 20:13

Ursus

2 Answers2