JavaScript Incorrect math

Asked Oct 14 '15 at 18:09

Active Dec 29 '15 at 15:53

Viewed 53 times

I have a very very straight forward math problem that is being done. The problem is JavaScript is telling me the wrong answer. After doing some reading, it is related to the https://en.wikipedia.org/wiki/Floating_point and https://en.wikipedia.org/wiki/IEEE_floating_point

However I do not know how to fix the problem really simply.

V = 118.3;
X = 22;
Y = 0.05;

z = (X * Y) + V;

In this case the answer should be 119.4 but JavaScript is telling me it's 119.39999999999999.

I have been looking but I can not seem to come up with a solution. Does anyone know how to fix, stop, predict, etc this weird "bug" of JavaScript?

edited Dec 29 '15 at 15:53

Jonathan Leffler

asked Oct 14 '15 at 18:09

Pyromanci

1

It's not JavaScript, it's binary floating-point math in general. – Pointy Oct 14 '15 at 18:12
It's not just a javascript phenomenon. – lintmouse Oct 14 '15 at 18:12
well regardless who or what is at fault how can get around this problem – Pyromanci Oct 14 '15 at 18:16
http://stackoverflow.com/a/3644354/502381 – JJJ Oct 14 '15 at 18:24
`Math.ceil(z * 10) / 10` does the trick. – ThomasReggi Dec 19 '15 at 07:45

0 Answers0