F01BRF Example Program Data
   6 15                                                           : n, nz
   5.0  1  1   2.0  2  2  -1.0  2  3   2.0  2  4   3.0  3  3
  -2.0  4  1   1.0  4  4   1.0  4  5  -1.0  5  1  -1.0  5  4
   2.0  5  5  -3.0  5  6  -1.0  6  1  -1.0  6  2   6.0  6  6      : a