Re: [Boost-users] library accumulator, example sum_accumulator

From: Kim Kuen Tang (kuentang_at_[hidden])
Date: 2008-09-03 14:01:41

Hi Eric,

thank you for your reply.

After studying the interface i see that this is an internal interface.
And this interface should be used internally.

The reason why i ask is that i want to implement an general static class 
in QuantLib, which should accumulate an vector, valarray or scoped_array.

I noticed that the class accumulator_set<> can not take a vector as 
sample. Is this true?
And do you plan to extend it to accumulate vector?

with regards,
Kim Tang

Eric Niebler schrieb:
> 
> Kim Kuen Tang wrote:
>> Hi all,
>>
>> i ' ve written a piece of code to get the class sum_accumulator 
>> working which is described in the user's guide
>> http://boost-sandbox.sourceforge.net/libs/accumulators/doc/html/accumulators/user_s_guide.html#accumulators.user_s_guide.the_accumulators_framework.extending_the_accumulators_framework. 
>>
>>
>> The function result must be provided with a struct dont_care.
>> And the constructor of dont_care must be provided with a value to get 
>> an instanciation.
>> In my opinion a default constructor taking no arguments  for the 
>> struct dont_care must exists so the user can write code like dont_care().
>>
>> To get the example working i must write code like
>> sumacc.result(*dont_care(0.0)*) to get the result from my accumulator.
>> And this is a little bit unnecessary.
> <snip>
> 
> The interface you're describing is an internal interface, consumed by 
> the accumulator_set<>. End-user code should never be directly calling 
> the result() member function of an accumulator implementation. 
> Accumulators are not supposed to be used stand-alone ... only as part of 
> an accumulator_set<>.
> 
> HTH,
>