Re: [Boost-users] Traversing through a multi_array and accessing the data set...

On Tue, 4 Sep 2007, Graham Reitz wrote:

How do you access the data in the example below?

Thanks much,

Graham

boost::multi_array multi_test; boost::multi_array::iterator multi_test_iter; boost::multi_array::extent_gen extents;

multi_test.resize(extents[2][3]);

for (multi_test_iter = multi_test.begin(); multi_test_iter != multi_test.end(); ++multi_test_iter) { // How do you get(set) at the current data set pointed to by multi_test_iter? }

multi_test_iter in this example is an iterator on rows. You need to add an extra loop to iterate on those elements, something like for ( multi_test_iter = multi_test.begin() ; multi_test_iter != multi_test.end() ; ++ multi_test_iter ) { for ( boost::multi_array< double , 2 >::value_type::iterator inner_multi_test_iter = multi_test_iter->begin() , end_inner = multi_test_iter->end() ; inner_multi_test_iter != end_inner ; ++ inner_multi_test_iter ) { // here, *inner_mult_test_iter returns a reference to a double } } -- François Duranleau