The sole purpose of this namespace is to be able to import all functions and symbols that are expected to be used within operator() for indexing and slicing. If you already imported the whole Eigen namespace:
Namespace containing all symbols from the Eigen library.
Definition Core:141
then you are already all set. Otherwise, if you don't want/cannot import the whole Eigen namespace, the following line:
is equivalent to:
using Eigen::all;
using Eigen::last;
using Eigen::lastp1;
using Eigen::fix;
auto seq(FirstType f, LastType l, IncrType incr)
ArithmeticSequence< typename internal::cleanup_index_type< FirstType >::type, typename internal::cleanup_index_type< SizeType >::type, typename internal::cleanup_seq_incr< IncrType >::type > seqN(FirstType first, SizeType size, IncrType incr)
Definition ArithmeticSequence.h:162
auto lastN(SizeType size, IncrType incr) -> decltype(seqN(Eigen::last-(size-fix< 1 >()) *incr, size, incr))
Definition ArithmeticSequence.h:331