Algebraic functions of rectangles and points can be used to check inclusion and intersection of such objects. Questions like "Are rectangles R1 and R2 disjoint?" or "Is point P outside or inside rectangle R?" can easily be answered.

• r1.intersects(r2): is True if r1 has a non-empty intersection with rectangle r2.

• r1.contains(x): is True if the rectangle or point x is contained in rectangle r1. This is equivalent to the expression x in r1.