def check_square():
I = Interval(0.0, 1.0)
P = PosetProduct((I, I))
assert P.get_bottom() == (0.0, 0.0)
assert P.get_top() == (1.0, 1.0)
assert P.leq((0.0, 0.0), (0.0, 0.5))
assert not P.leq((0.0, 0.1), (0.0, 0.0))
def check_square():
I = Interval(0.0, 1.0)
P = PosetProduct((I, I))
assert P.get_bottom() == (0.0, 0.0)
assert P.get_top() == (1.0, 1.0)
assert P.leq((0.0, 0.0), (0.0, 0.5))
assert not P.leq((0.0, 0.1), (0.0, 0.0))