python 0,1行列问题

shape[0]-- 行

A.min(0) --A的按列最小值,生成一个行向量

>>> a = np.random.rand(3,3)
>>> a
array([[ 0.97648289,  0.05062472,  0.11744009],
       [ 0.27388128,  0.33661322,  0.41430721],
       [ 0.46806654,  0.0443846 ,  0.81542961]])
>>> b = a.min(0)
>>> b
array([ 0.27388128,  0.0443846 ,  0.11744009])