1c981c48f5bc9aefeffc0bcb0cc3934c2fae179ddNarayan KamathMatrix4i m = Matrix4i::Random(); 2c981c48f5bc9aefeffc0bcb0cc3934c2fae179ddNarayan Kamathcout << "Here is the matrix m:" << endl << m << endl; 3c981c48f5bc9aefeffc0bcb0cc3934c2fae179ddNarayan Kamathcout << "Here is m.block<2,2>(1,1):" << endl << m.block<2,2>(1,1) << endl; 4c981c48f5bc9aefeffc0bcb0cc3934c2fae179ddNarayan Kamathm.block<2,2>(1,1).setZero(); 5c981c48f5bc9aefeffc0bcb0cc3934c2fae179ddNarayan Kamathcout << "Now the matrix m is:" << endl << m << endl; 6