1typedef Matrix<float,1,Dynamic> MatrixType;
2typedef Map<MatrixType> MapType;
3typedef Map<const MatrixType> MapTypeConst;   // a read-only map
4const int n_dims = 5;
5
6MatrixType m1(n_dims), m2(n_dims);
7m1.setRandom();
8m2.setRandom();
9float *p = &m2(0);  // get the address storing the data for m2
10MapType m2map(p,m2.size());   // m2map shares data with m2
11MapTypeConst m2mapconst(p,m2.size());  // a read-only accessor for m2
12
13cout << "m1: " << m1 << endl;
14cout << "m2: " << m2 << endl;
15cout << "Squared euclidean distance: " << (m1-m2).squaredNorm() << endl;
16cout << "Squared euclidean distance, using map: " <<
17  (m1-m2map).squaredNorm() << endl;
18m2map(3) = 7;   // this will change m2, since they share the same array
19cout << "Updated m2: " << m2 << endl;
20cout << "m2 coefficient 2, constant accessor: " << m2mapconst(2) << endl;
21/* m2mapconst(2) = 5; */   // this yields a compile-time error
22