
Boost Users : 
Subject: Re: [Boostusers] [Math] advice using brent_find_minima()
From: John Maddock (boost.regex_at_[hidden])
Date: 20141209 07:57:50
> I'd like to find the root of a function f (find x such that f(x) = 0).
>
> Should I pass abs( f ) to brent_find_minima()?
No: that's a truly lousy method for finding the root.
If you have one or more derivatives of f then use newton_raphson_iterate
or halley_iterate from
http://www.boost.org/doc/libs/1_57_0/libs/math/doc/html/math_toolkit/internals1/roots.html
Otherwise use toms748_solve or bracket_and_solve_root from
http://www.boost.org/doc/libs/1_57_0/libs/math/doc/html/math_toolkit/internals1/roots2.html.
Note that the latter of these two calls the former, which happens to
be asymptotically optimal if you have no derivative information.
And no, we don't have examples for these as they're "details" that
aren't officially part of the library yet. However, we really should do
something about that as the code has actually been stable for millennia
now ;)
HTH, John.
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