FUNCTION: RRep2Perm - calculate a permutation from its matrix in the regular representation

CALLING SEQUENCE:

RRep2Perm(m)

SG[RRep2Perm](m)

PARAMETERS:

m = a square matrix

SYNOPSIS:

• The RRep2Perm function calculates a permutation from its matrix in the regular representation, that is to say the matrix of the linear operator "left multiplication by perm".

• Whenever there is a conflict between the function name RRep2Perm and another name used in the same session, use the long form SG['RRep2Perm'].

EXAMPLES:

> with(SG):
> Perm2RRep([3,1,2]);
 
                              [ 0  0  0  1  0  0 ]
                              [                  ]
                              [ 0  0  1  0  0  0 ]
                              [                  ]
                              [ 0  0  0  0  0  1 ]
                              [                  ]
                              [ 0  0  0  0  1  0 ]
                              [                  ]
                              [ 1  0  0  0  0  0 ]
                              [                  ]
                              [ 0  1  0  0  0  0 ]
 
> RRep2Perm( Perm2RRep([3,1,2]) );
 
                                   [3, 1, 2]