Short-circuit Logic

[Ahmed Abdulshafy]

On Tuesday, May 28, 2013 2:10:05 AM UTC+2, Nobody wrote:
> On Mon, 27 May 2013 13:11:28 -0700, Ahmed Abdulshafy wrote:
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> 
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> > On Sunday, May 26, 2013 2:13:47 PM UTC+2, Steven D'Aprano wrote:
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> >
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> >> What the above actually tests for is whether x is so small that (1.0+x)
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> >> cannot be distinguished from 1.0, which is not the same thing. It is
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> >> also quite arbitrary. Why 1.0? Why not (0.0001+x)? Or (0.00000001+x)?
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> >> Or (10000.0+x)?
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> > 
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> > That may be true for integers,
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> 
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> What may be true for integers?
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> > but for floats, testing for equality is not always precise
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> 
> 
> And your point is?
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> 
> 
> What Steven wrote is entirely correct: sys.float_info.epsilon is the
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> smallest value x such that 1.0 and 1.0+x have distinct floating-point
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> representations. It has no relevance for comparing to zero.

He just said that the way to test for zero equality is x == 0, and I meant that this is true for integers but not necessarily for floats. And that's not specific to Python.