parseInt'ing Infinity with a radix

Question

I was reading twitter when I came across a tweet that said..

parseInt(1/0,19); //18

Of course, in JS, anything divided by 0 is Infinity, but what does the radix 19 mean, and why is Infinity radix 19 parsed to 18?

Other radix, such as 16, or 10 (default) will yield "NaN", so what's special about the radix 19?

Now try `parseInt(Infinity.toString() ,19)`, and see that you get the same result, so `Infinity` is irrelevant, it's converted to a string — adeneo, Aug 18 '14 at 19:34
@adeneo I forgot the function took strings. This suddenly makes a lot of sense. — Sterling Archer, Aug 18 '14 at 19:37

score 1 · Accepted Answer · answered Aug 18 '14 at 19:33

1

Upper-case letters are used in bases above 10, and I is the ninth letter of the alphabet. Thus, it's one less than 19.

answered Aug 18 '14 at 19:33

Pointy

1 Answers1