using namespace boost::numeric::odeint not working

Question

I'm trying to use the odeint-solver from boost, but I'm stuck at the very beginning with a stupid mistake, I can't seem to fix. I copied the boost-folder to my project-folder and using

#include <boost/array.hpp>

#include <boost/numeric/odeint.hpp>

using namespace std;
using namespace boost::numeric::odeint;

from an example-code, is already not working (include-files not found). Changing < and > to quotes (") works (visual studio finds the files). But "using namespace boost::numeric::odeint" does not (visual studio underlines "numeric"). I also tried putting the boost-directory (and even boost/numeric) in the project-properties additional include-folders, but still "numeric" isn't found. The files DO exist (and visual studio auto-completes them). Since this should be header-only, putting the folder in my project-folder and just #include'ing should work, right? But if the files are found, why isn't the "using namespace"-part working?

Sorry, if this is a stupid question ;-)

Answer 1

OK, I found my mistake. I'm leaving the question though, because maybe others make the same mistake:

So I simply had to copy boost_1_xy... (boost_1_78_0 in my case) NOT just the subfolder /boost withih this folder and then include the boost_1_xy-one. I assumed since all header-files are in there, this would be the needed directory (well ... it is, but I guess the header-files have their #includes relativ to the path "/boost"...).