HELP FOR: how contretableaux are represented in ACE

SYNOPSIS:

• This part describes how contretableaux are represented in ACE.

• First of all, the alphabet is the set of the integers. The order on the alphabet is the natural one, i.e. ... < -1 < 0 < 1 < 2 < ...

• A contretableau is represented as the list of its columns read from left to right and from top to bottom. Hence, lengths of these lists (columns) are in weakly increasing order. Moreover, each list (column) must be in decreasing order while if we read the contretableau row by row from left to right, values must be in weakly increasing order. 2 5 7 1 4 4 is represented by the list [[2,1], [5,4], [7,4,3]] 3

• The empty contretableau is denoted by the empty list.

EXAMPLES:

> ct:=[[2,1], [5,4], [7,4,3]]:
> CTab2Mat(ct);
 
                                 [ 2  4  7 ]
                                 [         ]
                                 [ 1  3  6 ]
                                 [         ]
                                 [       5 ]