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Re: Change definition of complex::norm



We might want to consider moving this over to the libstdc++ list, instead 
of gcc.

> Sorry, I forgot that the exponent range is not symmetric, the formula I
> gave for the absolute error tolerance is incorrect.  The smallest
> nonzero denormal in double precision IEEE is 4.940656e-324.  And in the
> example I gave, the answer in exact arithmetic is exactly halfway between
> 4.940656e-324 and 0.0, so there is little to choose between them.

I'm hoping Gaby will summarize this argument. 

I would think that this patch could go in, or be provided for float, 
double specializations of complex.

Can you generate a patch and post it to libstdc++@gcc.gnu.org?
Does this impact the performance noted here:

http://gcc.gnu.org/ml/libstdc++/2001-09/msg00091.html
http://gcc.gnu.org/ml/libstdc++/2001-09/msg00110.html



thanks,
benjamin


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