source: pacpussensors/trunk/Vislab/lib3dv-1.2.0/lib3dv/eigen/doc/snippets/MatrixBase_noalias.cpp

Matrix2d a, b, c; a << 1,2,3,4; b << 5,6,7,8;
c.noalias() = a * b; // this computes the product directly to c
cout << c << endl;