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My question is why choose the 7A5?

B.R.
徐晖

在 2013-8-7,下午6:26,Michael Richter <ttmrichter@gmail.com> 写道:

On 7 August 2013 17:36, 徐晖 <xuhui122000@gmail.com> wrote:
Hi guys,
Why the NNMARK is define to 0x7FF7A500? I have read the ieee 754-2008
std, the std just say that NaN's are represented by a bit pattern with
an exponent of all 1s and a non-zero mantissa. 0x7FF7A500 in binary
format is 0(sign bit) 11111111111(exponent of all 1s) 0(snan) 111 1010
0101(why?) 0000 0000. Can anyone answer my question? thanks.


I'm not sure I understand your question.  NaNs are exponents that are all 1 and a mantissa that is not zero.  0x7FF7A500 is a bit pattern that has an exponent that is all 1 and a mantissa that is not zero.  Where is the problem?


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