| Re: [eigen] Does c++ use of "norm" bother anyone else? |
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Hi
On Thursday 18 June 2009 11:44:47 Tim Hutt wrote:
> >> norm( complex<float>(3,4) ) == 25
>
> Wow that's really bad. I've never heard of this norm being used in
> mathematics. 'Norm' on its own virtually always means the L2 norm.
Quite often it just means "any norm" (given that in finite dimensions, all
norms are equivalent). But in math it certainly means that it satisfies all
properties of a norm, which L2-squared certainly does not (not scaling
properly, triangle inequality violated).
So in my opinion, it is a good idea to correct this mistake in C++ and not
support norm(), or maybe support it if a certain macro is defined (something
like EIGEN_COMPLEX_PROVIDE_DEFECTIVE_NORM).
Markus
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