Is it possible to get 0 by subtracting two unequal floating point numbers?

Question

Is it possible to get division by 0 (or infinity) in the following example?

public double calculation(double a, double          


        

Answer 1

You wouldn't get a division by zero regardless of the value of a - b, since floating point division by 0 doesn't throw an exception. It returns infinity.

Now, the only way a == b would return true is if a and b contain the exact same bits. If they differ by just the least significant bit, the difference between them will not be 0.

EDIT :

As Bathsheba correctly commented, there are some exceptions:

1. "Not a number compares" false with itself but will have identical bit patterns.

2. -0.0 is defined to compare true with +0.0, and their bit patterns are different.

So if both a and b are Double.NaN, you will reach the else clause, but since NaN - NaN also returns NaN, you will not be dividing by zero.