sq3 = Le(0, x) & Le(x, 3) & Le(0, y) & Le(y, 3)
sq4 = Le(1, x) & Le(x, 2) & Le(1, y) & Le(y, 2)
sq5 = Le(1, x) & Le(x, 2) & Le(1, y)
-sq6 = Le(1, x) & Le(x, 2) & Le(1, y) & Eq(y, 3)
+sq6 = Le(1, x) & Le(x, 2) & Le(1, y) & Le(y, 3)
sq7 = Le(0, x) & Le(x, 2) & Le(0, y) & Eq(z, 2) & Le(a, 3)
+p = Le(2*x+1, y) & Le(-2*x-1, y) & Le(y, 1)
+
+
universe = Polyhedron([])
q = sq1 - sq2
e = Empty
print('sq1 has {} parameters'.format(sq1.num_parameters()))
print()
print('does sq1 constraints involve x?', sq1.involves_dims([x]))
+print()
+print('the verticies for s are:', p.vertices())
+print()
+print(p.plot())