// row vectors are treated like a matrix with one row
  rowvec r;
  r << 0.59499 << 0.88807 << 0.88532 << 0.19968;
  r.print("r:");

  // column vectors are treated like a matrix with one column
  colvec q;
  q << 0.81114 << 0.06256 << 0.95989 << 0.73628;
  q.print("q:");

  // dot or inner product
  cout << "as_scalar(r*q) = " << as_scalar(r*q) << endl;

    // outer product
  cout << "q*r =" << endl;
  cout << q*r << endl;


  // sum of three matrices (no temporary matrices are created)
  mat F = B + C + D;
  F.print("F:");

    return 0;