Fractal dimension D tokens the degree of roughness of part terrain,; Variance shows the degree of terrain gurgitation,; Information entropy indicates the terrain variety in a certain direction.

• 分数维数表徵了局部地形粗糙的程度；方差值表徵了地形起伏的程度；作息熵表徵了在某一具体方向上的地形变化情况。