On Tue, 31 May 2011 22:41:36 +0100, Hannes Landeholm <landeh...@gmail.com>
wrote:
Agree with Derick, strictly speaking, in maths science, INF != INF.
I disagree,based on quote from
http://compilers.iecc.com/comparch/article/98-07-134:
"Since a projective infinity doesn't have a sign, comparing a floating
point value other than infinity to a projective infinity is unordered.
However, a projective infinity is equal to itself."
Yes, as I argued, for purposes of IEEE 754, it's certainly the case that
INF = INF.
This may not be true for certain meanings of "infinity" or notions of
ordering, but we have a standard for floating point arithmetic with
well-defined terms and rules which we ought to follow.
As a curiosity, Mathematica defines the result of Equal[Infinity,
Infinity] and Equal[Overflow, Overflow], but not for ComplexInfinity or
Indeterminate (similar to NaN):
In[1]:= ComplexInfinity == ComplexInfinity
Out[1]= ComplexInfinity == ComplexInfinity
In[2]:= Infinity == Infinity
Out[2]= True
In[3]:= Overflow == Overflow
Out[3]= True
In[4]:= Indeterminate == Indeterminate
Out[4]= Indeterminate == Indeterminate
--
Gustavo Lopes
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