FUNCTION: Perm2Inv - invert a permutation

CALLING SEQUENCE:

Perm2Inv(perm)

SG[Perm2Inv](perm)

PARAMETERS:

perm = any list denoting a permutation

SYNOPSIS:

• The Perm2Inv function inverts a permutation perm.

• Whenever there is a conflict between the function name Perm2Inv and another name used in the same session, use the long form SG['Perm2Inv'].

EXAMPLES:

> with(SG):
> Perm2Inv([3,1,2,4]);
 
                                  [2, 3, 1, 4]