doc/snippets/Tutorial_SlicingVec.cpp

RowVectorXf v = RowVectorXf::LinSpaced(20, 0, 19);
cout << "Input:" << endl << v << endl;
Map<RowVectorXf, 0, InnerStride<2> > v2(v.data(), v.size() / 2);
cout << "Even:" << v2 << endl;