Tutorial_simple_example_dynamic_size.cpp revision c981c48f5bc9aefeffc0bcb0cc3934c2fae179dd 
1#include <Eigen/Core>
2#include <iostream>
3
4using namespace Eigen;
5
6int main()
7{
8  for (int size=1; size<=4; ++size)
9  {
10    MatrixXi m(size,size+1);         // a (size)x(size+1)-matrix of int's
11    for (int j=0; j<m.cols(); ++j)   // loop over columns
12      for (int i=0; i<m.rows(); ++i) // loop over rows
13        m(i,j) = i+j*m.rows();       // to access matrix coefficients,
14                                     // use operator()(int,int)
15    std::cout << m << "\n\n";
16  }
17
18  VectorXf v(4); // a vector of 4 float's
19  // to access vector coefficients, use either operator () or operator []
20  v[0] = 1; v[1] = 2; v(2) = 3; v(3) = 4;
21  std::cout << "\nv:\n" << v << std::endl;
22}
23