Javascript - Remove leading zero from string

Question

This is probably a super easy one. But I've got a series of numbers which looks like this:

0.12704174228675136
0.3629764065335753

I want to remove the leading 0. and keep only the two first numbers, so this is the result:

12
36

But I don't know how to round numbers . Usually, I'd convert it to a string and use regular expression. I guess I could do that now as well, but since I've got numbers here, I mind as well learn this now.

Answer 1

If they're already strings, substr 'll do the trick:

str.substr(2, 2);

If they're numbers, you can multiply and use Math.floor :

Math.floor(number * 100);

Answer 2

The fastest and easiest way:

number*100|0;

( | is bit wise OR and it will convert any number to an integer, thus behaving the same as Math.floor but shorter and faster.)

Answer 3

a couple of ways to do this

Math.floor(number*100);

Probably the most correct as you are working with a number the whole time.

parseInt(number*100, 10);

parseInt is supposed to take a string as first argument, but if you pass it a number javascript will convert to string.

(number+"").replace(/\d*\.(\d{2})\d*/, "$1");

Or convert to string and regex