: ludec(a=(1,3,5\2,4,7\1,1,0),l=.,u=.,p=.)

: a
       1   2   3
    +-------------+
  1 |  1   3   5  |
  2 |  2   4   7  |
  3 |  1   1   0  |
    +-------------+

: l
        1    2    3
    +----------------+
  1 |   1    0    0  |
  2 |  .5    1    0  |
  3 |  .5   -1    1  |
    +----------------+

: u
         1     2     3
    +-------------------+
  1 |    2     4     7  |
  2 |    0     1   1.5  |
  3 |    0     0    -2  |
    +-------------------+

: p
       1
    +-----+
  1 |  2  |
  2 |  1  |
  3 |  3  |
    +-----+