# From this -
weight     area    cost
1              2          3.17
2              2          3.87
3              2          4.51
4              2          5.22

# To THIS:
$cost{2} = {
                      1     => 3.17,
                      2     => 3.87,
                      3     => 4.51,
                      4     => 5.22,
                      [...]
};