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A comment on How many floating-point numbers are in the interval [0,1]?. Parent comment

Re:How many floating-point numbers are in the interval [0,1]? by digga3000 on Wednesday March 01, 2017 @07:02PM (#13770006)
the question is [0, 1] so wouldn't that include +/-0 and 1, so 3 more?
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Re:How many floating-point numbers are in the interval [0,1]? by jacobolus on Wednesday March 01, 2017 @07:13PM (#13770103)
Probably shouldn’t include –0, which is used to represent underflow of negative numbers.
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Re:How many floating-point numbers are in the interval [0,1]? by vog on Thursday March 02, 2017 @03:38AM (#13772615)
Why 3 more? Grandparent already counted one of the border points, so the correct number is either 1 more or 2 more, depending on whether you consider the floating point number -0 to be in the closed interval [0,1] or not.

See my other posting for more details: https://news.ycombinator.com/item?id=13772578

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Re:How many floating-point numbers are in the interval [0,1]? by nine_k on Wednesday March 01, 2017 @07:13PM (#13770104)
-0 is "below zero, but for so little that we cannot represent", so it's outside [0, 1].
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Re:How many floating-point numbers are in the interval [0,1]? by kr7 on Wednesday March 01, 2017 @07:32PM (#13770224)
Though for the purposes of comparisons, -0 and +0 are the same in IEEE 754.

So the expression "x >= 0.0f && x <= 1.0f" is true for x = -0.

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