http://www.boost.org/doc/libs/1_43_0/doc/html/accumulators/user_s_guide.html#accumulators.user_s_guide.the_statistical_accumulators_library.covariance

I don't understand the call "acc call". I would like to rebuild the cov command form Matlab for matrix data (http://www.mathworks.com/access/helpdesk/help/techdoc/ref/cov.html).

If this is correct, when I give as the first argument of command data from the first line and second as the data of the first column to the first value to calculate the new matrix?

I try try compile the excample, but I get a compiler error on the "acc::tag::covariate1":

acc::accumulator_set<double, acc::stats<acc::tag::covariance<double, acc::tag::covariate1> > > xx;

xx(1., acc::tag::covariate1 = 2.);

xx(1., acc::tag::covariate1 = 4.);

xx(2., acc::tag::covariate1 = 3.);

xx(6., acc::tag::covariate1 = 1.);

std::cout << acc::covariance(xx) << std::endl;

The error text: "expected primary-expression befor = token". Sorry, it's a little bit late, so I don't see my mistake

Thanks Phil