ground/gcs/src/libs/eigen/doc/snippets/Tutorial_AdvancedInitialization_ThreeWays.cpp

   1 const int size = 6;
   2 MatrixXd mat1(size, size);
   3 mat1.topLeftCorner(size/2, size/2)     = MatrixXd::Zero(size/2, size/2);
   4 mat1.topRightCorner(size/2, size/2)    = MatrixXd::Identity(size/2, size/2);
   5 mat1.bottomLeftCorner(size/2, size/2)  = MatrixXd::Identity(size/2, size/2);
   6 mat1.bottomRightCorner(size/2, size/2) = MatrixXd::Zero(size/2, size/2);
   7 std::cout << mat1 << std::endl << std::endl;
   8
   9 MatrixXd mat2(size, size);
  10 mat2.topLeftCorner(size/2, size/2).setZero();
  11 mat2.topRightCorner(size/2, size/2).setIdentity();
  12 mat2.bottomLeftCorner(size/2, size/2).setIdentity();
  13 mat2.bottomRightCorner(size/2, size/2).setZero();
  14 std::cout << mat2 << std::endl << std::endl;
  15
  16 MatrixXd mat3(size, size);
  17 mat3 << MatrixXd::Zero(size/2, size/2), MatrixXd::Identity(size/2, size/2),
  18         MatrixXd::Identity(size/2, size/2), MatrixXd::Zero(size/2, size/2);
  19 std::cout << mat3 << std::endl;
  20