[Boost-users] [Accumulators] How to define the initial value ?

Subject: [Boost-users] [Accumulators] How to define the initial value ?
From: Adrien Todeschini (adrien.todeschini_at_[hidden])
Date: 2010-10-08 11:58:26

Hi everyone,

As the code of weighted_sum_impl constructor is

[ in header <boost/accumulators/statistics/weighted_sum.hpp> ]
template<typename Args>
weighted_sum_impl(Args const &args)
  : weighted_sum_(
        args[parameter::keyword<Tag>::get() | Sample()]
          * numeric::one<Weight>::value
    )
{
}

and the template parameter Tag is defined as tag::sample

namespace tag
{
    struct weighted_sum
      : depends_on<>
    {
        typedef accumulators::impl::weighted_sum_impl<mpl::_1, mpl::_2,
tag::sample> impl;
    };
}

How can I define this tagged argument when initializing the accumulator_set
?
( Indeed, weighted_sum_impl constructor is called at this point )

Thanks in advance for your help.

Adrien