Can you compare floating point values exactly to zero?

Question

I know we can\'t compare 2 floating point values using ==. We can only compare they are within some interval of each other. I know

if(val == 0.512)


        

Answer 1

For comparison with err all you need to is.

// compare a and b with an ERR error.
if (Math.abs(a - b) <= ERR)

To compare with 0

// compare a and 0 with an ERR error.
if (Math.abs(a) <= ERR)

Answer 2

I would still recommend following the tolerance idiom and not compare to zero exactly.