Algorithms and algorithm analysis of logical OR operation of variable precision upper approximation operator and grade lower approximation operator

This paper is to construct new operation of approximation operators, and explore its calculation. First it proposes logical OR operation of variable precision upper approximation operator and grade lower approximation operator. Then regular algorithm and structural algorithm are proposed and analyzed, and furthermore it obtains an important conclusion that structural algorithm has advantages in space complexity. Finally the new operation and its algorithms are explained by a medical example.