| typedef Matrix<float, 1, Dynamic> MatrixType; |
| typedef Map<MatrixType> MapType; |
| typedef Map<const MatrixType> MapTypeConst; // a read-only map |
| const int n_dims = 5; |
| |
| MatrixType m1(n_dims), m2(n_dims); |
| m1.setRandom(); |
| m2.setRandom(); |
| float *p = &m2(0); // get the address storing the data for m2 |
| MapType m2map(p, m2.size()); // m2map shares data with m2 |
| MapTypeConst m2mapconst(p, m2.size()); // a read-only accessor for m2 |
| |
| cout << "m1: " << m1 << endl; |
| cout << "m2: " << m2 << endl; |
| cout << "Squared euclidean distance: " << (m1 - m2).squaredNorm() << endl; |
| cout << "Squared euclidean distance, using map: " << (m1 - m2map).squaredNorm() << endl; |
| m2map(3) = 7; // this will change m2, since they share the same array |
| cout << "Updated m2: " << m2 << endl; |
| cout << "m2 coefficient 2, constant accessor: " << m2mapconst(2) << endl; |
| /* m2mapconst(2) = 5; */ // this yields a compile-time error |
