FUNCTION: Compo2Mat - a planar representation of a composition

CALLING SEQUENCE:

Compo2Mat(compo)

COMP[Compo2Mat](compo)

PARAMETERS:

compo = any list denoting a composition

SYNOPSIS:

• The Compo2Mat function gives the diagram of a composition (i.e. a skew diagram of width 1, also called a ribbon), in the cartesian plane.

• A composition is a list of strictly positive integers.

• The following option is allowed:
  'alphabet' = l where l is a list of 1 to 3 components, l[1] filling the skew diagram, l[2] the inner diagram and l[3] the outside.

• Whenever there is a conflict between the function name Compo2Mat and another name used in the same session, use the long form COMP['Compo2Mat'].

EXAMPLES:

> with(COMP):
> Compo2Mat([4,2,1,5]);
 
                         [ 1  1  1  1  1  0  0  0  0 ]
                         [                           ]
                         [ 0  0  0  0  1  0  0  0  0 ]
                         [                           ]
                         [ 0  0  0  0  1  1  0  0  0 ]
                         [                           ]
                         [ 0  0  0  0  0  1  1  1  1 ]
 
> Compo2Mat([4,2,1,5], 'alphabet'=[`#`,`.`,` `]);
 
                         [ #  #  #  #  #             ]
                         [                           ]
                         [ .  .  .  .  #             ]
                         [                           ]
                         [ .  .  .  .  #  #          ]
                         [                           ]
                         [ .  .  .  .  .  #  #  #  # ]