0.1 + 0.2 !== 0.3 WTF?
Don't take my word for it, try it in the console.
(its actually 0.30000000000000004) <- for teh lazies
Here is a tip that might prevent some headaches in the future.
When doing floating point math, add some extra checks, such as rounding off the number or checking for the difference as well.
There is an issue with floating point math and computers in general, and you may not get the desired results without some safeguards. You can read more about it here:
http://docs.oracle.com/cd/E19957-01/806-3568/ncg_goldberg.html
TL;DR
Basically your computer does math with 1's and 0's. It is really hard to represent certain (floating point) numbers with binary. It makes mistakes ;)
Written by Peter Peterson
Related protips
2 Responses
That's really bad. :)
In JavaScript you can use Number#toFixed method, like that:
Number((0.1 + 0.2).toFixed(2)) === 0.3
# trueCoderwall badly needs "protip already exist":
http://coderwall.com/p/gy3ayw?i=13&p=1&q=author%3Aavnerner&t%5B%5D=avnerner
