Decreased( tbl, reducibles, mat )
Decreased( tbl, reducibles, mat, choice )
tries     to      solve   the    output      of    OrthogonalEmbeddings
OrthogonalEmbeddings  or    Extract   Extract in   order   to  find
irreducible characters.  tbl must  be  a character table,  reducibles
the  list of characters used  for  the call of OrtgogonalEmbeddings  or
Extract, mat one solution, and in the  case of a solution returned by
Extract, choice must be the corresponding choice component.
Decreased returns a record with components
irreducibles:
remainders:
matrix:remainders
      component, which could not be solved.
    # see example in "Extract" 'Extract'
    gap> d := Decreased( s4, y, e.solution[1], e.choice[1] );
    rec(
      irreducibles :=
       [ [ 1, 1, 1, 1, 1 ], [ 3, -1, -1, 0, 1 ], [ 1, -1, 1, 1, -1 ],
          [ 3, 1, -1, 0, -1 ], [ 2, 0, 2, -1, 0 ] ],
      remainders := [  ],
      matrix := [  ] )
GAP 3.4.4