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Re: complex number
On 2009-04-01 14:48Z, Marco Atzeri wrote:
>
> I was trying to understand why this code
>
> #include <iostream>
> #include <complex>
>
> int main()
> {
> double a = 0;
> double b = 1. / a;
> a += 1;
> std::cout << std::abs (std::complex<double> (b, a)) << '\n';
> }
>
> produce Inf on most platform and NaN on cygwin.
As I read C++2003 26.2/3, this use of std::abs has undefined
behavior, so NaN would be conforming even though Inf would
be less surprising.
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