1 #include <Eigen/Dense>
2 #include <iostream>
3 
4 using namespace Eigen;
5 using namespace std;
6 
main()7 int main()
8 {
9   ArrayXXf  m(2,2);
10 
11   // assign some values coefficient by coefficient
12   m(0,0) = 1.0; m(0,1) = 2.0;
13   m(1,0) = 3.0; m(1,1) = m(0,1) + m(1,0);
14 
15   // print values to standard output
16   cout << m << endl << endl;
17 
18   // using the comma-initializer is also allowed
19   m << 1.0,2.0,
20        3.0,4.0;
21 
22   // print values to standard output
23   cout << m << endl;
24 }
25