Math.min()

[Ransika deSilva]

Hi!,
System.out.println(Math.min(-0,0));
Why does this print 0, instead of -0.0. I am asking becuase in the Math class -0 < 0 and in the same time the min() returns a double value.So there should be a fractional part as well. Don't you think so.
Thank you very much..

[Vicken Karaoghlanian]

ransika, first of all the signatures for the Math.min() methods are:
min(double,double) returns double
min(float,float) returns float
min(long,long) returns long
min(int,int) returns int
And secondly, negative zero is not less that positive zero, as a matter of fact they are both equal.
System.out.println(-0 == 0);
Now when you call Math.min(-0,0) the 4th overloaded method is invoked (the one which return integer), thus outputting positive zero because integer and long values doesn't have an implementation for negative zero (float and double values do implement negative zero however).
Hope this helps.

[Yan Lee]

From the JLS:
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"Positive zero and negative zero compare equal; thus the result of the expression 0.0==-0.0 is true and the result of 0.0>-0.0 is false. But other operations can distinguish positive and negative zero; for example, 1.0/0.0 has the value positive infinity, while the value of 1.0/-0.0 is negative infinity."