1        1     2.0
  1        2     3.0
  1        3     1.0
  2        1     0.0
  2        2     9.0
  2        3     0.0
  1        1     2.0
  3        1    -5.0
  3        2     2.0
  1        1     1.0
  3        3    -7.0
  1        1     1.0