From: Gennadiy Rozental (gennadiy.rozental_at_[hidden])
Date: 2007-02-16 02:19:37


"Dave Steffen" <dgsteffen_at_[hidden]> wrote in message
news:17875.30459.786153.370572_at_yttrium.numerica.us...
> Jody Hagins writes:
> > On Wed, 14 Feb 2007 09:59:46 -0700
> > Dave Steffen <dgsteffen_at_nu
> >
> >
> > > Well, I don't think it's that bad. It's just not what I need for the
> > > mathematical work I do.
> >
> >
> > Maybe you can explain how it is to be used, then? Another perspective
> > may help...
>
> OK, I'll try. Is the problem "what is a relative error" or "how do I
> use the existing macros to test relative error"?

relative error of value f1 in comparison with value f2 id defined as

rel_err = (f1-f2)/f1;

If we little simplify the situation

BOOST_CHECK_CLOSE_FRACTION( f1, f2, t )

checks that value f1 in comparison with value f2 do not exceed t.

In really it a one more step. it checks that relative error in both
direction (strong check) do not exceed t.

Gennadiy