This command computes the dimension of the polyhedral set polyset.  The point has dimension 0, the line dimension 1, etc.  By convention, -1 is the dimension of an empty polyhedral set.

$\mathrm{with}\left(\mathrm{PolyhedralSets}\right)\:$

$\mathrm{Dimension}\left(\mathrm{ExampleSets}:-\mathrm{Tetrahedron}\left(\right)\right)$

$3$

$\mathrm{es}≔\mathrm{ExampleSets}:-\mathrm{EmptySet}\left(3\right)\:$$\mathrm{Dimension}\left(\mathrm{es}\right)$

$\mathrm{-1}$

The PolyhedralSets[Dimension] command was introduced in Maple 2015.

For more information on Maple 2015 changes, see Updates in Maple 2015.