Re: Generic compile-time summation (possibly using Boost)
on Sun Jun 21 2009, Martin Eisenberg <martin.eisenberg-AT-udo.edu> wrote:
Alon K wrote:
template<int N>
struct Power
{
static inline double result ( const double x)
{
return x * Power<N-1>::result(x);
}
};
template<>
struct Power<0>
{
static inline double result ( const double x )
{
return 1;
}
};
FYI, you should use the Russian Peasant algorithm in the Power<N>
functor to mimimize template instantiation depth, because of both
implementation limits and compilation speed. Similar considerations
may apply to your other functors; in particular, tree-like
instantiation nestings are preferable over linear nestings.
I know how to generate a tree-structured recursive exponentiation
(though not an optimal one). However, all the references I can find to
the Russian Peasant algorithm are about multiplication and not
exponentiation. Care to elaborate on your suggestion?
--
Dave Abrahams
BoostPro Computing
http://www.boostpro.com
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