[ublas] When I can not use two prec_prod's?

Subject: [ublas] When I can not use two prec_prod's?
From: Peng Yu (pengyu.ut_at_[hidden])
Date: 2008-10-19 12:35:53

Hi,

The following code would not compile. Can somebody let me know what the
problem is?

Thanks,
Peng

#include <boost/numeric/ublas/matrix.hpp>
#include <boost/numeric/ublas/io.hpp>

int main () {
  boost::numeric::ublas::matrix<double> m(2, 2);

  m(0, 0) = 1;
  m(1, 0) = 2;
  m(0, 1) = 3;
  m(1, 1) = 4;

  std::cout << prec_prod(m, prec_prod(m, m)) << std::endl;//error
}