def dmp_sub_ground(f, c, u, K):
 return dmp_sub_term(f, dmp_ground(c, (u - 1)), 0, u, K)

def dmp_sub_ground ( f , c , u , K ) : return dmp_sub_term ( f , dmp_ground ( c , ( u - 1 ) ) , 0 , u , K )
subtract an element of the ground domain from f .