waht is -0.0?

[ego hu]

Mock Exam:
What is displayed when the following is executed:
double d1 = -0.5;
System.out.println("Ceil d1 = " + Math.ceil(d1));
System.out.println("floor d1 = " + Math.floor(d1));
Answer: -0.0, -1.0.
I compiled and run, it is true.
So what is the difference between -0.0 and 0.0?

[Bala Arul]

In my opinion, 0.0 is equals to -0.0. Sign only indicates how the zero was achieved, whether from positive or negative value.
B Arul

[Stevie Kaligis]

Hi Ego...
0.0 & -0.0 :
1. they both are Floating Point Literals.
2. they considered equal when you use (0.0 == -0.0)
3. but produce different result when used in some calculation.
for example :
(1.0/0.0) produces positive invinity, and
(1.0/-0.0) produces negative invinity.
hope this help
stevie