Matrix3i m = Matrix3i::Random(); cout << "Here is the matrix m:" << endl << m << endl; cout << "Here is the upper-triangular matrix extracted from m:" << endl << Matrix3i(m.triangularView<Eigen::Upper>()) << endl; cout << "Here is the strictly-upper-triangular matrix extracted from m:" << endl << Matrix3i(m.triangularView<Eigen::StrictlyUpper>()) << endl; cout << "Here is the unit-lower-triangular matrix extracted from m:" << endl << Matrix3i(m.triangularView<Eigen::UnitLower>()) << endl; // FIXME need to implement output for triangularViews (Bug 885)