
 
Compares the Cartesian coordinates of points p and q lexicographically in $$xy order: first $$xcoordinates are compared, if they are equal, $$ycoordinates are compared.  

 
Compares the Cartesian coordinates of points p and q lexicographically in $$xy order: first $$xcoordinates are compared, if they are equal, $$ycoordinates are compared. 