m.randn(20)

In [196]: arr
Out[196]: 
array([-0.2047,  0.4789, -0.5194, -0.5557,  1.9658,  1.3934,  0.0929,
        0.2817,  0.769 ,  1.2464,  1.0072, -1.2962,  0.275 ,  0.2289,
        1.3529,  0.8864, -2.0016, -0.3718,  1.669 , -0.4386])

In [197]: np.partition(arr, 3)
Out[197]: 
array([-2.0016, -1.2962, -0.5557, -0.5194, -0.3718, -0.4386, -0.2047,
        0.2817,  0.769 ,  0.4789,  1.0072,  0.0929,  0.275 ,  0.2289,
        1.3529,  0.8864,  1.3934,  1.9658,  1.669 ,  1.2464])</code></pre>
<p>当你调�