a=np.array([[[1,1],[2,2],[3,3]],[[4,4],[5,5],[6,6]],[[7,7],[8,8],[9,9]],[[10,10],[11,11],[12,12]]])print aprint a.shapeb=a.mean(0).shapec=a.mean(1).shaped=a.mean(2).shapeprint bprint cprint d

output:

[[[ 1  1]  [ 2  2]  [ 3  3]] [[ 4  4]  [ 5  5]  [ 6  6]] [[ 7  7]  [ 8  8]  [ 9  9]] [[10 10]  [11 11]  [12 12]]](4, 3, 2)(3, 2)(4, 2)(4, 3)