Re: Rice distribution

[Ed Smith-Rowland <3dw4rd at verizon dot net>]

On 09/05/2012 10:29 PM, Ulrich Drepper wrote:
> On Wed, Sep 5, 2012 at 6:34 PM, Ed Smith-Rowland <3dw4rd@verizon.net> wrote:
> > I wrote some distributions a couple months back.  I wrote them as
> > (name-uglified) extensions to libstdc++.
> >
> > Here is the Rice distribution.
> I never used this distribution myself but that doesn't mean anything.
> A few nits:
>
> - you should add __generate functions (see the current svn code)
Forgot about that.  Fixed.
> - in the operator function, did you consider using hypot?  I'm not
> sure it's necessary, the x and y numbers might not require it.  hypot
> is usually more accurate.  The multiplications are throwing away a lot
> of bits which the sqrt call might need.
Hypot is a good idea.  I'm not worried about overflow heresuch as student-t.
> - the operator== has the bug which we fixed in the library.  You
> cannot define a template friend function in the template class
> definition.  Look at the current libstdc++ code.  Likewise for the
> other friend functions.
i think I got this right.  Other distros have things as I have them here.
> - how about moving the operator() code and perhaps even the operator==
> code into random.tcc?
They are small.  i left them where they wre but I could still move them.
> - move the operator!= outside the class definition, just like for the
> other classes
Done.
> - with the definition being in ext/random, the test cases shouldn't
> reference the non-existing rice_distribution.h header
I sent an old patch I guess.  Fixed.

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