Re: [Boost-users] Template instantiation function arguments and Boost.Preprocessor

From: Ovanes Markarian (om_boost_at_[hidden])
Date: 2008-01-29 03:30:41

sum_arr_copy_accumulate is wrong. Array should be passed as copy. (I don't
know what's going on with me these days). Sorry for spamming the group...

Timing of copying the array and calling accumulate:

sum_arr_copy_accumulate
50.15 s

result: 2.84756e+10

Best Regards,
Ovanes

On Jan 29, 2008 9:25 AM, Ovanes Markarian <om_boost_at_[hidden]> wrote:

> Seven,
>
> thanks a lot for pointing it out. That was a classical error!! :(
>
> Anyway I re-ran the test, with corrected accumulate calls:
>
> corrected calls:
> array_type::value_type sum_carr_accumulate(array_type const& a)
> {
>     return std::accumulate(a.begin(), a.end(), 0.0);
> }
>
> array_type::value_type sum_arr_copy_accumulate(array_type const& a)
> {
>     return std::accumulate(a.begin(), a.end(), 0.0);
> }
>
> Results (which would be expected from std lib ;)
>
> Running each test 4294967295 of times:
> --------------------------
> sum_arr_copy
> 64.79 s
>
> result: 2.84756e+10
> --------------------------
> sum_carr
> 14.91 s
>
> result: 2.84756e+10
> --------------------------
> sum_arr_copy_accumulate
> 14.91 s
>
> result: 2.84756e+10
> --------------------------
> sum_carr_temp_result
> 14.91 s
>
> result: 2.84756e+10
> --------------------------
> sum_carr_accumulate
> 14.91 s
>
> result: 2.84756e+10
> --------------------------
> sum_doubles_copy
> 15.00 s
>
> result: 2.84756e+10
> --------------------------
> sum_doubles_copy_optimized
> 14.96 s
>
> result: 2.84756e+10
> --------------------------
> sum_doubles_copy_temp_result
> 14.92 s
>
> result: 2.84756e+10
> --------------------------
> sum_doubles_ref_temp_result
> 14.97 s
>
> result: 2.84756e+10
> tests done
>
>
> Regards,
> Ovanes
>
>
>
>
> On Jan 29, 2008 5:42 AM, Steven Watanabe <watanabesj_at_[hidden]> wrote:
>
> > AMDG
> >
> > Ovanes Markarian wrote:
> > > array_type::value_type sum_carr_accumulate(array_type const& a)
> > > {
> > >     return std::accumulate(a.begin(), a.end(), 0);
> > > }
> > >
> > > array_type::value_type sum_arr_copy_accumulate(array_type const& a)
> > > {
> > >     return std::accumulate(a.begin(), a.end(), 0);
> > > }
> > >
> >
> > > Please take a look, that accumulate produced wrong result.
> >
> > Of course.  The results are being collected in an int...
> >
> > In Christ,
> > Steven Watanabe
> >
> > _______________________________________________
> > Boost-users mailing list
> > Boost-users_at_[hidden]
> > http://lists.boost.org/mailman/listinfo.cgi/boost-users
> >
>
>