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QVM: Quaternions, Vectors, Matrices

mag(vec)

#include <boost/qvm/vec_operations.hpp>

namespace boost
{
    namespace qvm
    {
        //Only enabled if:
        //  is_vec<A>::value
        template <class A>
        typename vec_traits<A>::scalar_type
        mag( A const & a );
    }
}

Returns:

The magnitude of the vector a.