This is not a huge problem as if you are outputting the floating point number, you would probably want to round it anyways. The biggest 'gotcha' is when doing equality comparisons between these numbers.
Consider the following:
.1 + .2 == .3 // false
The way to 'get around' this is to have a value (usually called an epsilon) that is relative in magnitude to the numbers being compared. In this example, a value like .00001 as epsilon should work fine.
Anyways, all you have to do is check if the absolute difference of the numbers is less than the epsilon:
var a = .1 + .2, b = .3, epsilon = .00001;
console.log(Math.abs(a-b)<epsilon); // true
In short, try to not put yourself in a situation where you have to compare equality with doubles.
Consider the following:
The way to 'get around' this is to have a value (usually called an epsilon) that is relative in magnitude to the numbers being compared. In this example, a value like .00001 as epsilon should work fine.Anyways, all you have to do is check if the absolute difference of the numbers is less than the epsilon:
In short, try to not put yourself in a situation where you have to compare equality with doubles.